I've had to try a lot of coping skills to see what personally works for me.
Currently, I do a lot of self-soothing. I hug myself, my stuffed animals, curl up in a fetal position, lay in the grass since I love nature.
I also have my "safe places" I go to like the park, library, a certain area of the town, etc. I have a tendency to self-isolate so I try to challenge that and make a small goal to go out, which also helps my depersonalization/derealization.
For self-harm or suicide thoughts, I sometimes will watch comforting ASMR roleplay videos, or I'll write it out in poetry to give the emotions somewhere to exist, since I often hide how I'm feeling IRL. I also have my comfort shows or videos I can have on in the background, when it's hard to focus on anything in life, I have these things I can at least put on and I try not to judge myself for not being able to do much. When I was really going through the worst of it, I did a pros/cons list to try to look at the consequences of acting or not acting, and I would also try to go by the "take it 20 minutes at a time" if I was struggling on an hour-to-hour basis.