First thing that comes to mind is to worry less. If you're shy because you might be considered you'll say something stupid, or do something stupid keep in mind that we all do. No human being can be right about everything all the time. We all do and will make mistakes. Sometimes big ones. Sometimes small ones.
The saying practice makes perfect has a grain of truth in it. The more you do something the better you'll get at it. Unless of course you have some serious issues you previously didn't know about. In which case practicing will show those issues to you if your self aware enough.
I say this a lot. Like a lot a lot. Try your best to be as logical as you can. Most of dating and talking to other human beings has a certain large amount of rejection involved. It's a numbers game. There's a very long list of reasons or excuses people will have for why you aren't their type. Not talking just romantic relationships either. Even when it comes to friendships people still carry the same influences they do in romantic relationships.
And the last thing i can think of right now. Be your own best friend first. Be able to enjoy your own company while no one else is around. That's a good general rule by itself but it becomes important ten fold when dealing with other human beings in any capacity. You will be rejected, you will be attacked, you will have people attempt to paint you as things you are not but odds are also good that you won't. That you'll be the one who has to reject someone else.
If you like yourself, enjoy your own time with yourself and it never gets to the level of narcissism you'll be able to navigate other people, interact with them and so on without many large issues. And will be able to handle large amounts of what you have to deal with without internalizing it. Sure, if something is logical. Takes cues from it. Most of all though. Be kind. To yourself and others. When you can.
