Influencing someone is a social attack. Make an Influence roll (CHA, MANIP or APP + Ability) vs Resolve. Page 215.
Instill: Try to force a new intimacy upon someone. Declare the idea you want to instill. ST will levy any penalties, up to -5 on the attempt. If successful, target gains a new Minor intimacy. This can be used to strengthen or weaken existing intimacies, but only if the argument presented is more compelling than what generated the intimacy initially.
Persuade: Compel a target to perform certain tasks. The level of your intimacy with them will determine the level of tasks you can convince them to do. If you have no intimacy with them, they can only be convinced to perform the most trivial of tasks.
Bargain: Compel a target to perform a task in exchange for something. Does not rely on intimacies.
Threaten: Compel someone to do (or not do) something in exchange for you NOT doing something, typically inflicting bodily harm. This can also potentially instill a negative intimacy.
Inspire: Uses Performance and picks an emotion to target. You can convince someone to form a new passion or act on an existing intimacy.
Read Intentions: (PER + Socialize) vs Guile to determine what is motivating someone during a scene. This can also determine someone's Intimacies, and the character should declare what sort of Intimacy they are trying to find before rolling. ST should tell them if they succeed but the target has no Intimacies that fit the description.