1) Look to see if she is wearing any clothing or jewelry that might give you a clue.
Is she wearing a plaid shirt, a beanie, or some other item of clothing associated with lesbians? What about a rainbow ring or necklace? If she is, she is at least a sympathetic to lesbian relationships if not gay herself. If she isn't, not necessarily a problem. Some girls aren't into advertising.
2) Check her fingernails.
It is highly unlikely a woman with long, sharp fingernails is a lesbian. If her fingernails are long but she seems gay, check her middle finger and/or her index finger. If these two only are trimmed, chances are she may be a lesbian.
3) Mention the name of a local gay or lesbian bar or club and ask if she has ever been there.
If she says she has been there, you're golden. Go ahead and ask her out! Don't give up right away if she has never heard of the place, though. She may just be new in town or not "out."
4) Notice how she talks about men.
Bring up something about guys to see how she reacts. It's not foolproof (lesbians are not necessarily man-haters and straight girls sometimes sound as if they are), but it could be helpful.
5) Mention your "last girlfriend" and see how she responds.
If there is no look of shock or obvious change in her demeanor, she at least is open to the idea of lesbian relationships.
6) If you are near a coffee shop or bar, ask her if she'd like to go for coffee or a drink..
If she accepts your invitation and sits and talks with you, then she is probably as interested in you as much as you are in her.
7) Does she make eye contact with you?
If she maintains eye contact a little longer than normal, especially if she smiles, she may be interested in you as more than a friend.
8) Does she play with her hair when she talks and smiles at you?
This is often the way a very feminine woman will flirt. Look for subtle changes in her facial expressions and her eyes. Hair flipping or twisting, along with the above, are almost certain signs that you are being flirted with.
9) Does she touch your arm or brushed against you at all?
If she is trying to move into your space, this could be a possible signal. If you return the gesture and she leans into you, it is a pretty sure sign that she is thinking what you are thinking.
10) Casually place your hand on the small of her back and direct her towards a door, a chair, or anywhere.
If she readily moves with you, her subconscious is allowing you to take control of the situation, and it indicates her desire for you to do so. At that point, you should be confident enough to ask her for her number so that you can "give her a call sometime."
If all else fails, you could just come right out and ask her, of course. If that's not really your style, though, these ten signs should be enough to tell you if she is gay or straight, and if she is interested in you. Even if she does turn out to be straight, maybe you can at least make a new friend.
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