I channel my rage into passive-aggressiveness on a sliding scale. Being verbal about what is pissing me off helps, but with a focus on the thing, and not the people (as best I can). .. And maybe venting my rage at my stream audience sometimes. For entertainment. I work with politicians and bureaucrats, that'll learn you new levels of hate and anger :D Then the day-to-day rage doesn't seem so bad anymore.

For yourself and anger issues, though, it's difficult to give suggestions without know what's boiling beneath. Could try mental focusing, focus more on solutions when things are against you, rather than fuming about the problems. If it's fixable, fix it, if it's not, fuck it, basically, mitigate the damage and solve things. Less fucks given = More fucks available for important things. Keeping in mind how much energy you spend on being angry at something can also help you stay more aware of your mental state. On the whole, though, it's all in the mind and mentality of the individual. Which isn't very helpful, but y'know..

Edit: Also, drawing violent things.. :p

it depends on what kind of angry outburst specifically, but. i have a tendency to lose my temper over sometimes really stupid shit and its ended up getting me hurt more than once lol. as an example i can think of i couldnt get a cabinet to close at work the other day and i ended up slamming it shut as hard as i could in frustration which hurt my arm a lot and gave me a headache from the sound etc.

what i do if i can kinda feel that starting to come on is ill stop myself mid-action and just tense up whatever part of my body (arm, leg, shoulder, w/e) and hold it tensed for a few seconds with a deep breath and then relax it breathing out and just give myself a few moments before i go back to what i was doing. actually physically tightening part of my body REALLY helps and holding my breath for a second focuses my mind on that instead. its not foolproof and i cant even initiate the process sometimes but it does help most of the time when i can actually get it going

i dont know if that technique would apply for you, but even just in general maybe the "let yourself tense up and then breath it back out" part might help? i think thats included in general mindfulness/coping stuff but i havent done any of that 'officially' so i wouldnt know for sure lmao

as a general thing idk if you watch youtubers/streamers much, but when im having a really bad depression episode i usually put on a laughter compilation from game grumps or something similar and it almost always makes me smile/laugh at least a little even if im still feeling bad overall!

I related to this nearly every day

Especially in reference to being angry at a person or how a system works, I do one of two things. The first is that I rant and rave about it in the car to no one, and the second often more effective one is to do my best to put myself in the other person's shoes. What kind of day are they having? What sort of stresses or problems do they have internally or externally? If it's a corporation or a government thing, any organization really, I try to figure out what system might be working against me and why it might be set up that way.

Essentially, I try to understand the thing that's frustrating me, learn about it if I don't know, and try to digest it. Doesn't work for some things, but it super helps with people and organizational shit. I get less mad when I understand the mechanism, usually. Occasionally I have to go a layer deeper than normal, but the goal is to get to a point where I can accept how the person or system acted to affect me particularly, and why I do or don't matter on their scale of things.

Ultimately, I'm a bit player in everyone else's story, just as much as they might seem like nobodies to me. Being mad at shit I can't change will just make my life shorter and less happy. I let things slide because, honestly, a lot of it doesn't matter.