Just do it.
… Seriously. Just do it. Unless it’s something stupid like jumping a bunch of cars with your motorcycle, the best thing you can do is just do whatever it is you’re scared to do. Telling someone you like them? Do it. Approaching an intimidating teacher or boss? Do it. Applying for a new job? Moving out? Attending therapy?
Just do it. You might need to compose yourself, put yourself in a better frame of mind. That’s fine. You’re scared; it’s natural to prepare yourself. But in the end… well, you just need to do it. If you don’t, your fear will turn into overthinking. And we all know what overthinking can do.
So just do it.