Hi, I have been doing this for as long as I can remember too and, coincidentally, just found something that really helps.
I was thinking several things,
first, how just doing any activity with my hands wasn't enough, I'd stop doing whatever it was and pick at something instead,
then, about how people compare skin picking to an addiction and the whole dopamine and reward thing,
and I thought, I need some kind of hand puzzle, or something that does something when I touch it,
so I bought a Rubik's cube and it helps a lot! As long as I use it, it keeps me from picking. I don't have to always try to solve it either, just moving it around also works.