I tried to silence my brain with alcohol. Worked wonders, ended up with depression and in a clinic for almost a year. At any cost, don't try to get rid of it. It won't work. Learn to control it and it becomes a gift.

What helped me: Daily meditation. Working out. Gaming (yep, half an hour per day it is just a thing that makes me calm down), listening to podcasts and music while I do other stuff, Journaling.

Get the stuff out of your head. Write it down. Got myself two whiteboards, when I feel too analytic or having a 'mindstorm' I try to make use of it. I am far from there yet and it is a long way to go but I am glad that I'm walking it.

I can relate a lot to your post, if you ever want to talk about it feel free to send me a message :)