You should NEVER approach a girl and ask her out if it's so clear that she doesn't like you. If she says she hates you, it means she hates you. The second way to show that is by her body language. Look for signs showing that she likes you before asking her out.

Sometimes she actually flirts with you using her body language. If you are able to read her intentions, then it will be more convenient to you to take her out on a date. Here's a few positive body language by her :

One : Her eyes and the way she looks at you :

She's looking at you longer than she's supposed to, it would create an awkward moment. NEVER EVER look away if you like her. Just stare back with intense feeling.

You can see her pupils are dilating. Which means either she's dying or she's having a romance aura at that moment. You're definitely in good position to ask her out. Or to kiss her.

She gives you an invitation to approach her by lifting up one of her eyebrows while looking at you.

Two : Her lips.

She licks her lips. She wants you, man. She definitely wants you!

She smiles most of the time when talking to you. And you can feel that her smile is sincere.

Three : Her hair

She plays with her hair while talking to you. If she's making round moves while playing with her hair, she's actually flirting with you, man! Approach her, fool! Approach her now! Sometimes she's even being bold by brushing her long beautiful hair onto you.

Four : Her body posture

She crossed her legs towards you. That's a good sign. But nowadays it's a common. You'll have to look for another sign.

She heaves her chest outwards. That's one of her female's secret weapons to lure you.

She leans her body over you to get closer. That's a good sign. If her body touches you when she leans, that's even better.

Five : Others

She takes up every opportunity to touch you when talking.

She smiles and laughs a lot but not to the extent of ridiculing you.

She asks many questions indicating that she's really interested to communicate with you.

But of course, there's still a 5 to 10 percent chances that she still rejects you when you asks her out. It's either she's teasing you and playing a hardball OR she already has a boyfriend. It's your call. Bite the bullet or find another babe!