How do boys act around girls they like?

Each individual is different but some common things most guys share in common are;

Eye contact. If he likes you, he may either look away quickly if he is shy, or he'll try to catch your eye and hold it until you look away first.

Listen to what he's saying. If he likes you, and he's nervous, he'll probably start talking about himself. Many times, guys feel the need to prove themselves; especially if you talk about another guy in his company.

Be aware of touching. He might put his hand on your arm when he laughs, and won't move his leg if it happens to touch yours, or he may hug you for small things - all are good signs of a guy liking you, unless he's a bit of a "playboy" who flirts with a lot of girls.

Watch his actions around other girls and see if he treats you differently.

Watch for him showing interest in things you like and do. For example, if you like a certain genre of music that he likes as well, he may suggest bands or artists for you to listen to.

Check for signs of nervousness. Nervous laughter, sweaty palms, deep breaths, fidgeting, looking away quickly when you notice if he is watching you are all good signs of an attraction towards you and that he is nervous about making an impression on someone he fancies.

Pay attention to his friends. If they know he's interested in you, they might tease him subtly when you're around, hint to you that he likes you, or even try to find out if you like him.

Look to see if he imitates you If he mimics you, he probably likes you, such as, if you move to another table, he'll go with you.

Teasing If a guy teases you a lot, it might mean he likes you, but if he doesn't tease any other girl, he probably does like you.

Keep in mind the only way to know for sure is to ask him.

MY opinion, not yours.

Cheers.

Every guy is different when he is intersted he will always have an excuse to talk to you, try to make you laugh, keeps eye contact with you (but if he is shy he would look down) he will eventually ask for your number or give his number to you. He will try to be around you all the time even for a little excuse.