Control Behaviors

Controllers will do whatever it takes to stay in control. Their goal is control, not whatever the goal, activity, or situation is; the project or activity, or relationship is secondary, or may not even be a real goal.
That's why none of your requests or suggestions, opinions, or needs are taken as valid. If they went along with something you requested, suggested, or initiated, that would mean (to them) that you are in control, and they're not. It's also why they try to "take over" whatever you're doing when you ask for their assistance instead of ASSISTING you. It's also why they always have to be "right", and you always have to be "wrong", and it's also why they always want to be the one who "knows more" or has "more experience", regardless of reality.
(They can become very taxing with constant announcements about "things they know" during social conversations, or during any kind of discussion; they seem to see conversation as a competition or an opportunity for displaying one's knowledge, instead of a respectful exchange of information, thought, or feeling and humor. So they may always be trying to "top" you or counter whatever you're saying; they may assume that you're trying to display your knowledge also to compete with them or "top" them.).

They will do things purposely in order to stay in control, such as

~withhold information
~change things around
~give skewed or negative feedback about one's work or project
~give skewed or negative feedback about one's character
~give skewed or negative feedback about one's judgment
~discard, destroy, or give away one's possessions or work
~change times and schedules so they're the one who's "in charge",
~counter anything one says,
~deny one's suggestions and requests,
~claim credit for another's work or idea
~invalidate things one says and expresses,
~not respond,
~stand a person up,
~leave a person out,
~deny one's basic physical needs; make it difficult to obtain them
~refuse to share resources or be unavailable after implying they wanted to "help" (even if helping is their job),
~turn activities into exclusive clubs for only certain types of people
~give "misinformation"
~gossip, triangulate, slander
~act tough
~speak abusively
~talk loudly on purpose
~interrupt, talk over others
~put others down
~cast "blame" for anything and everything
~cast shame for anything and everything
~exaggerate physical problems to get sympathy, leniency, or resources
~make up physical problems to get the above
~deny training, mentoring, instruction
~demean a student while instructing them
~deny proper tools and materials
~deny space or time to work
~deny peace to concentrate
~deny peace, time, space, or care to recover from injury, whether physical or emotional

These are all Control behaviors, either for trying to gain control, or trying to maintain it. There are many more of course, with varying behaviors and degrees of severity; this is a basic list.

Controllers learn to do these things and how to do them because their main goal is gaining or keeping control. So they learn by trial and error, and by watching others, just like one would learn how to do anything else. They can and do learn other things as well, skills, knowledge, etc., but everything they do is always subject to and within the parameters of the motive of control.