Choleric people are the proud, extroverted 'alphas' of our species.
Cholerics people are leaders and directors. They seek to be in control of situations, to be on top, to be the best.
This doesn't necessarily mean that they are all driven to reach the top of the corporate ladder or anything, or that they all want to have leadership roles, but in day-to-day interactions with other people, they have a tendency towards one-upsmanship.
They use imperative, commanding language, wording things as orders rather than requests. Compare "get me a drink" to "can I have a drink?". They probably use phrases like 'deal with it', 'get over yourself', 'stop being such a wimp', etc, or may start sentences with "look", or maybe "look, buddy" or "listen, pal" or things like that.
They word things with confidence and certainty. Compare "X is this way" to "maybe X is this way, or something?".
They are firm and forceful in their approach to problems. They believe in 'tough love', and try to 'help' others by challenging them to prove themselves, as they themselves would.
They're more likely to tell someone who they are trying to 'help' that they're pathetic, expecting the person to say 'no, I'm not pathetic, I'll show you!', as indeed a choleric would in response to such a thing.
If met by opposition, they react confrontationally to defend themselves. They are constantly trying to be 'dominant' in every situation, subconsciously, either by being louder and better than those around them, or more restrained and therefore superior to those who lose their cool.
Most bullies are choleric, but few cholerics are bullies. Many will in fact stand up to those who bully others, rather than letting them get away with things.
Their confidence and demanding natures make them natural leaders, though this doesn't mean that they would necessarily enjoy leadership positions; they're just more likely to take charge if necessary rather than fumbling around worrying.
They will 'challenge' others aggressively in order to show their respect for the person's strength. They believe that it is important to 'prove oneself'.
They have a tendency to argue for reasons that are different to the melancholic. They're more driven by a desire to prove themselves greater than whoever they're arguing with, to assert that they are right, rather than to reach some kind of truth or compromise. They can lie in order to maintain the dominant position. The argument is about them moreso than the issue; a battle of egos rather than a quest for truth.
They say things like "if anyone tries to mess with me, I make them wish they'd never started on me in the first place".
They love competition... but hate to lose.
They are defiant of authority, challenging them as if to knock them off the top spot and assert their own dominance as the alpha of this pack, the leader of this tribe.
They can be very condescending to those that they look down upon.
They may take pleasure in the pain, misfortune, or humiliation of people they are not on good terms with. This is because it brings them pleasure to feel superior to others. "Haha! Look at that loser messing up! Hilarious!" (Compare this with the phlegmatic, who'd be more likely to feel distress when seeing someone being harmed, even if it was their worst enemy.)
Words like 'hot-blooded', 'brash', 'domineering', 'overbearing', might be used to describe this temperament.
They blame others for their own mistakes, often to the point of lying to save face.
They feel that they can define and understand and advise others, but laugh at the thought that others could do the same to them. This is because analysing and defining another puts you in the superior position, while being defined would put them in the inferior position, which they resist.
Cholerics are extroverted in the sense that they will meddle in others' affairs and 'speak their mind' if they feel it is necessary, rather than minding their own business.
They generally respond well to new situations, and seek thrills.
They seek to prove themselves externally, to show that they are great and the best and things like that. They must prove that they are strong.
They believe that it is important to 'say things how they are', to be bluntly honest about their opinions rather than 'sugar-coating' them.
They speak their mind, but often don't mind their speech.
Their pride and drive for dominance, as well as their open expression of emotion, naturally leads to outright aggression when challenged. They will raise their voices and get angry to show that they are the biggest and strongest, and to assert superiority.
They brag and boast to show how amazing they are, in an 'I am better than others' kind of way.
They are pragmatic, doing what needs to be done bluntly rather than worrying about fantasy scenarios.
They will plough through obstacles that bar their path (metaphorically speaking); they are single-minded in moving towards their goals.
They generally believe that they are right, and have immense stubbornness about admitting their flaws, UNLESS admitting these flaws would make them look better than others ("I'm strong enough to admit I'm wrong, unlike you").
They demand respect from others, and will hold grudges against those that they consider to be rivals.
They can be great, supportive friends who'd take a bullet for those close to them, unless you get on their bad side, in which case they'll try their best to 'rub your nose into the dirt'.
It is important to them that they are strong and courageous, not afraid of anything. If they are afraid, they will deny it (again, unless admitting it makes them look strong).
They often - but not necessarily - have high self-esteem.
They will 'rise to the challenge', in order to prove themselves, and look for opportunities to do so.
It's important for them to be tough and strong.
They are in many ways the opposite of the phlegmatic in that they are controlling, assertive, and see conflict and challenge and competition as a desirable form of interaction.
They have similarities to the melancholic in that both are stubborn and opinionated, but the choleric is more forceful and 'tough' while the melancholic is uncertain and sensitive.
Cholerics strive for independence, because to be dependent is to rely on others, to not be in the superior position. Dependence is weakness.
They are 'thick-skinned', in many cases bulletproof against the criticisms of others, able to shrug or laugh them off.
In our distant ancestors, the choleric members of the pack would be the alphas, the leaders. They would command their subordinates, and assert their dominance using force. If challenged, they would respond by getting angry, larger, in order to intimidate and to prove that THEY were the strongest, the most fit to lead.
In current society, they often tend towards leadership roles, such as managers, politicians, captains, team leaders, and so on, though not necessarily. In fantasy, they might be the proud warriors, the esteemed Kings.