Bombshell, You have always seemed to me to be a very open and friendly gal, anyway. Some people just have a harder time than others opening up to people like you seem to do naturally. But-- we all admire it. It is definitely a talent.
I think one thing that helps people to make friends is not to think ill of people, generally, but to look at them as a resource and a load of talent, or another way to say it-- personal gifts.
Another thing that's important is the ability to catch and remember names. That's a real talent in some people, and others have trouble even remembering their own (me). So for those people I have a suggestion: Every time you forget someone's name, ask them again. Tell them that you've always had trouble and you are trying to learn to recall names better, so if they don't mind, every time you forget their name you will just ask it again, because you like to hear it, and you'd like to know them better, too (or, something like that).
Be kind. You can still be saucy, clever, funny, factual, erudite, etc. but always let the foundation be a genuineness and fondness for them. No personality is worth a damn unless it's based in thoughtfulness and unselfishness, first. Folks will seek YOU out.
Don't be embarrassed, but be humble, admit your stupidity and toss it off. People like you for that, but they are watching to see what you can do, to. They want to know if you're worth anything, and what your talent(s) is.
Can you admit you're ever wrong? Is it easy, or hard to do? Ifr it's hard to do, you need to decide that you're not such a big shot and you don't know much, anyway. let other people tell you a thing or two. Admit you didn't know something, once in awhile.
"Iron sharpeneth iron. So a man sharpeneth the countenance of his friend."
Friendship is a two-way street. Unless you can give as much as you receive, you'll never amount to much as a friend. And there's all different kinds of friends. I don't suggest just makeing friends that fish, or that do woodworking, although that's the way to start. Friends should broaden your interests. That means, you have to make an effort to do things that you wouldn't normally do. You have to show enthusaism, but enthusaism is as contagious as the measles, and even if you start by faking it, pretty soon you catch it, yourself.