Building a Gaydar

I was reading a post on “girly girls” and how it’s so difficult to meet them because it’s easy to assume they’re straight. So, someone said, “Work on your gaydar” and I thought, “Yes! How did I not think of that?” Then, though, I quickly realized there’s probably not a how-to book at Barnes and Noble on building a gaydar. I know there have been discussions about what girly girls can do to send out indicators but what about honing our skills to pick up those signals? I think it’s also exceptionally hard for me because I’m such a “girly-girl” myself and maybe they don’t send out the message as strong because they assume I’m straight as well. What do you think? How do you know a girl is into you when you're not at a club but at say, Blockbuster? Are there meditation exercises or breathing techniques I should be doing? Maybe I just need new contacts…