The Ventrue toolset is built, above all, to ensure one thing: a Lord bows to no one. Dominate is the most obvious and powerful example of this idea at work, as a Ventrue skilled in this Discipline commands the actions, memories, and even thoughts of all those around him--mortal and Kindred alike--as easily as a puppeteer tugging on strings. But their other tools are also geared toward this end, too. Resilience is the most lordly of physical Disciplines, ensuring that no adversary gets to see the Ventrue broken. And many people seem to forget that the Ventrue are also masters of Animalism--and thus as competent at employing animal minions as the more obviously nature-attuned Gangrel.
Kindred of the Ventrue Clan thus, from a social standpoint, tend to be among the most savvy, aggressive, and dangerous characters in all the World of Darkness--whether those characters were social powerhouses in life or not. Remember, Disciplines can just as well help to shore up a character's weaknesses as bolster their strengths; a petulant, spoiled brat who couldn't persuade her way out of a paper bag before the Embrace now has the power to simply demand what she wants--and actually get it.
It's fortunate for the Ventrue that they're so good at wielding their proxies, because while all vampires benefit from proxy warfare, no Clan is more reliant upon such tactics than the Ventrue. Resilience, while useful, doesn't allow direct power over others they way Vigor and Celerity do; so when a Lord is forced to deploy his supernatural powers, he's really a one-trick pony, because the first and best line of defense is always to send a minion. Kindred of other Clans have tools to directly fight, escape, or avoid detection, but the Ventrue thrives by not being on the front lines in the first place. A Nosferatu will defend her haven by rising from sleep to twist the environment with Obfuscate and terrify her foes with Nightmare; a Ventrue doesn't bother rising from sleep, because her ghouls and thralls defend her. If those lines of defense fail, the Ventrue had better hope that she can Dominate her foes into leaving her alone, or that Resilience will weather the storm--but this is a disadvantageous position to be in.
In short, the ability to manipulate others is the Ventrue's greatest strength--and his reliance upon minions to get anything done is his greatest weakness. Playing a Ventrue effectively requires a solid grasp on this principle.
Finally, a word on the Clan Bane: because of their penchant for dominion over others, the Ventrue see mortals as tools more readily than any other Clan, and as such, like any compulsive sociopath, have as hard a time relating to them. Touchstones are less meaningful to these Kindred; downward spirals into lower levels of Humanity are a greater risk as the vampire becomes accustomed to thinking of people more as disposable puppets than sentient beings.
Thomas takes care of his Vitae and financial needs simultaneously. First he finds a wealthy-seeming individual on the street; from there, all it takes is a little eye contact. "Follow me," he says, and leads his new pet into an alley. There, he simply demands his victim's possessions one at a time. Give me your watch. Give me your wallet. Give me your phone. I like your tie--give me that, too. "You were mugged," he says, once he's done. He instructs the man to bare his throat; he steps in, embraces him, and takes his tithe of blood. As the victim shakes off the mind control, contending with the disorientation of the Kiss, Thomas hands the empty wallet to the nearest kine on his way out. "You robbed this man," he says. "Run."
Devon's dog, Rudy, is a magnet for good samaritans. Feral Whispers and the Vinculum have allowed her to train this animal to wander the streets at night seeming lost and in need of aid, and a collar or an occasional Lost Dog flyer posted around the neighborhood helps to complete the picture. Devon's food comes calling without her having to do anything; and when her lost dog is returned to her, she feeds from and dismisses the charitable mortal with a simple pair of commands: "Kiss me" and "I rewarded you."
When Joshua and his allies need a lot of Vitae, this Entombed Iron Edict allows for delivery: "The first time each night that you are contacted by a friend or family member, you will arrange to meet them at this location at 10PM. Once the two of you arrive in this room, you will stand in this corner and face the wall for five minutes. Then you will relocate the body to this closet and go straight home." At the end of the week, when the Dominated mortal has brought the fourth or fifth victim, Joshua opens the closet door for his pet to see, and pins the responsibility on to him with a simple memory alteration: "You killed these people."
The first and most important tip for playing a Ventrue effectively is that everyone you meet is a potential resource to be exploited. Get used to looking at people (and animals!) in this way. Since everyone you meet is a potential servant, you should constantly consider yourself to be on the lookout for more servants. Thus, every conversation becomes a sort of information-gathering and grooming session. When you meet a new person, try to determine what their assets are--what they have that might be useful to you later, whether that be personal resources or a certain skill set. It's trivially easy to learn details of this kind with innocuous everyday questions. What do you do for a living? Hmm, interesting.
As you converse with people, try to get a sense of their psychology, too. What kinds of relationships do they have? What kinds of past experiences? How morally flexible are they? The answers to these questions will give you insight into what sorts of actions would constitute Breaking Points for these characters--a key thing to know when you employ Dominate, as triggering a Breaking Point will snap your victim out of their Mesmerized state prematurely.
That said, while you should constantly be preparing to use your powers to subjugate others, try to be as sparing with these tools as you can realistically be. The Ventrue toolset is not subtle; a Ventrue who goes around Dominating everyone she meets is bound to run into trouble before long. Often it's much better in the long run to manipulate people (and animals!) as best you can without resorting to Disciplines. This is particularly true when you're dealing with fellow Kindred, who are more able to resist and notice your efforts to Dominate them.
Be paranoid, and try to plan ahead for as many contingencies as you can. More than any other Clan, the Ventrue are extremely vulnerable if they get caught alone or unprepared. Make sure you have several layers of security to hide behind, and aim to surround yourself with loyal, maintenance-free servants. Animalism is even more your friend here than Dominate; a loyal dog to wake you up or defend you while you sleep, or a bird to keep watch and warn you of potential interlopers, is a tremendous asset. But don't neglect human servants, either--a skilled and devoted thrall or ghoul is worth her weight in gold to a Ventrue.
Merits are your friend. Allies. Retainer. Safe Place. Haven. Herd. Take them. Love them.
Dominate is easily a candidate for most powerful Discipline in the game, but only if you're creative with it, and only if you understand the mechanics. Let me give you some help with the latter.
Mesmerize is the simplest but most valuable manifestation of Dominate. Everything else that you do extends from this ability; every other power in the Discipline requires that you use this one first, and most of the other powers don't even require any dice rolls at all, which means that your Mesmerize dice pool is by far your most important. (This makes the Expression Skill probably the most powerful skill in the game for a Ventrue, by the way.)
Inflicting the Mesmerized Condition requires eye contact, but this is only one way--the victim needs to the see the Kindred's eyes, not the other way around. This means the only way for the victim to avoid being Dominated is to be blind, or to cover or avert his eyes completely away from the vampire. (Sorry, Mr. Vampire Hunter, but those mirrored shades you bought are useless unless the vampire herself is wearing them.) Note too that inflicting this Condition only requires the slightest momentary eye contact, and no spoken command--that means you don't risk looking stupid by giving commands that aren't followed. The victim only becomes aware of what is happening if the activation roll is a Dramatic Failure.
The Mesmerized Condition, once it takes hold, will last for an entire scene (!), during which time you may issue as many commands as you want. By default, the victim won't clearly remember anything that happened while he was Mesmerized, but you can also use short commands to alter his memory of the scene further ("I was never here" is perhaps the most common and useful example of this type of command). The only way the Mesmerized Condition ends prematurely is if the victim suffers a Breaking Point or some type of physical harm. If the Condition gets broken in this way, it can be really difficult to reapply it in the same scene, so this is where the real finesse of Dominate comes into play: you want to avoid making your victim do anything that would be severely uncomfortable--or if you do, let it be the last instruction you give.
Note that instructions and false memories must be confined to what is concrete and observable. You can control your victim's thoughts to a minor extent, but emotions are out of bounds. "Write down your address" is fine, but "Write me a poem" is not; the former is simple and concrete, while the latter requires creativity and emotion. Similarly, "my performance was impressive" is legitimate, but "you loved my performance" is not; the vampire can ensure that her victim remembers her in a certain way, but cannot force an emotional reaction to those memories. (The victim could find the vampire's performance impressive, but still hate it, or the vampire, for some other reason.)
Most of the rest of the powers of Dominate are pretty straightforward, but one final important distinction: the Dominated Condition that is inflicted by Iron Edict differs from Mesmerized in two important ways: 1) It lasts much longer (until sunrise), and 2) it is confined to a single command. This is why the example from the book ("Follow my instructions exactly as I give them to you") is so powerful: it effectively turns the Dominated Condition into a longer and more elaborate version of the Mesmerized Condition. Note, though, that this effect would require the Kindred to stay around and continually give instructions until she is done; once she leaves, and the last instruction is followed, Dominated expires. That's the trade-off--had she given one single, but very involved command, she could have walked off and left the victim to it.
Resilience is probably the simplest Discipline in the game, so there's not much to explain--but don't forget about its active component! You can spend a Vitae when you are hit to negate some--or even all--of the damage.
Finally, let's talk about the most underrated Discipline in the entire game: Animalism. For whatever reason, people just seem to forget about this Discipline. It's incredibly good! Just read what the 3rd, 4th, and 5th dots of this Discipline do--no, really, go look at the book and read them! A vampire with Animalism 5 is the absolute master of his territory, the supreme lord of the land. And there's no reason that these powers need to be confined to the wilderness, either; a Kindred can claim dominion over a park, a sewer, or a penthouse suite equally well--and from his seat of power he can control dogs, cats, rats, birds, and people. Wondering how you defend your haven with complete supremacy? How to lure your enemy into an inescapable trap? Animalism is how.
That said, I'd like to make special note of Raise the Familiar, because it's probably the most overlooked power within the most underrated Discipline. This ability allows you to Embrace animals. These undead creatures are smarter, hardier, and more tenacious than they were in life. They require nothing except your blood, and they are automatically loyal to you. They can understand complex commands, and you can control them telepathically (!) and at any distance (!!). These dead animals make the perfect servants, and the best part is that there is no penalty to raising them (no Humanity cost, like there is with Embracing a human), no limit to how many you can raise (except how much Vitae you're willing to invest), and unlike a childe or even a ghoul there is zero chance that this minion will betray you. To put this into perspective for you, a Ventrue with a 2-dot Discipline and a few points of Vitae can have a greater number of more loyal, more powerful, better controlled, and longer-lasting animal minions than all but the most powerful of Thyrsus Mages.
If I can leave you with one thought, it should be that. Animalism is amazing. Take Animalism.