Anyone who enters a bar or party should come equipped with a flashing beacon over their head, explaining why they’re there—for a “good time” or just to hang out with friends. No such luck. Instead, men need to rely on other, more subtle cues, such as body language, clothing and facial expressions. For tips on how to read a woman’s “signs,” we reached out to behavior expert Lillian Glass, Ph.D.

She Smiles
Green light!”If she doesn’t smile at you, she’s likely not into you,” Glass says.

Her Shoulders Are Rounded
Abort! She’s feeling insecure. “Good posture means a woman has a good sense of self, is confident, and is very positive,” Glass says.

She Dressed to Thrill
A woman’s attire tells you exactly how she perceives herself and how she wants you to see her. “If she looks really hot, then she put in that effort to attract a guys,” Glass says. It doesn’t matter if she’s got on a banging dress and stilettos, or a tattered T-shirt and jeans. Hot is hot, and she wants attention.

The ‘Do
“If her hair is pulled down in her face, she’s hiding,” Glass says. Handle with caution. Conversely, when a woman tosses, flips, or plays with her hair, it’s a universal sign of flirting.

Her Companions
“A pack of women are generally too focused and involved—there’s too much eye contact going on between them,” states Glass. Don’t make a move. Two women together are ripe for the picking, especially if they’re looking around the room.

“Ready” Signs
“If a woman is arching her back and sticking her breasts or pelvic area out, it’s indicative of sex,” Glass says. If she’s pointing those things in your direction, you’re a lucky man. “It’s like saying, ‘I’m into you, and I’m not sexually inhibited.'”

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