Until I wasn't, I was straight. And I believe this is the case for many women. You don't realize you want to pursue a woman for more than friendship until you do. But once you know, there's a lot more to learn. And I don't mean that in a derogatory sense.
I was pretty afraid when I started dating the first woman I ever dated (shout out to my wife). I didn't know how to act, what to say, or when to touch something. There are so many unstated regulations that deciphering them would take a cryptologist. A lesbian cryptologist, to be precise. The reason for this is because women are complicated, yet in the greatest possible way. (Disclaimer: If you're dating the proper person, there aren't any rules.)
So now that I'm in a committed relationship with a woman, and I'm still quite good at dating, I've compiled a list of things I wish I had known when I first started dating a woman. If you or someone you know is interested in becoming a lesbian (or queer, bisexual, none of the above, or whatever word you like), this book is a wonderful place to start.