Ladies, how do you let (or not) a guy know you like them without being to obvious?

I'm kind of shy, so I tend to become really shy around a guy I like. I may act overly nervous or awkward around him. If we're alone, sometimes it helps, other times it makes it worse. I might open up more, but there might be a lot of awkward silences. When I am at ease, I am all smiles, might end up staring at him, and will listen to anything he says to the exclusion of other people. I try to be around him, though it might be more as a watcher from a distance than right up in his presence. I remember little things he says, details he mentions about his life, and may take up interest in things he likes. I definitely care about what he finds important, and will try to show that I remember these things by bringing them up in conversation again.

If I am feeling especially bold, I might try to make some physical contact, like brushing up against him a little if we are sitting together. Even if I am not initiating the contact, I would definitely let him touch me though. I am not normally a really physical person, so other people (and him, if he knew me well at all) would probably notice that I am allowing someone to touch me.

I usually don't tell anyone about a crush for a while at first, but I do eventually tell one or two close friends. At the least, people know something is up even if they don't know exactly WHO I like, so talking to my friends would give it away too.

If I like them, then I will flirt and make it a little physical. If I don't like them, then I will likely talk about another guy in front of them. Nothing lets a guys know you're not interested more than talking about how you think other guys are cute. I would also probably not return phone calls. As bad as that is, I have been guilty of that in the past.