You're just shy .. that's OK. But if you want to be more friendly, smile more and people will react better.
It's amazing how people react when you smile at them and say "Hello". That's a pretty easy start ...
Ah, yes . . . people look at me, for example a clerk, a waitress, a fellow plane passenger, or just walking by and from their initial ex
Learn several really good jokes that most people would like, then use them often, the stoic look on your face when you deliver the joke will make it more funny, they will laugh then you will smile then they will get to know you better. Just walk up to somene, "wanna hear a good joke....". Most people will say yes.