It can be exciting when a boy is flirting with you, but it can also be difficult to determine whether his behaviour is actually flirtatious. The way every boy flirts is very subjective, so what may be considered flirting for one boy may just be another boys way of being friendly. If he is displaying a few of these signs, follow your instincts to decide whether or not he's flirting.
Is he teasing or making fun of you? Men like to tease women to catch their attention, and establish a quick rapport with them. Women are often noted as saying that they are more attracted to men that aren't "the nice guy". Making fun of the way a woman acts draws attention to her, and lets her know that he's noticing her, and wants to show off his sense of humour. If a man is teasing you, he most likely isn't sincere, but trying to make you flustered, and make you "redeem" yourself to him.
Is he showing off? Some men feel that it's important to impress you with how great they are before they make their move. They may feel that you're out of their league, or that they need to impress you immediately to make an impression. By letting you know how great they are, they are also covertly putting down other men and establishing themselves as an alpha male. The main thing they want you to know [or believe] is that they're a great catch.
Is he complimenting you? Many men will simply tell you outright that they think you're attractive, smart, funny, or are wearing a particularly nice shirt that day. Throwing in these positives will make you think of him positively, and see him as someone who can brighten your day and treat you well.
Is he making a lot of eye contact, or playfully touching you? Boys who are interested in you will inadvertently make gestures to connect with you. If he's glancing in your direction a lot, or making direct eye contact, he's probably attracted to you and wants to see as much of you as possible. Glancing at you and then looking away quickly will also gain your attention, and make you engage in the back in forth so that you're participating in a quiet game of cat and mouse. If he's reaching out to touch you, he's probably trying to get closer to you, and engage with you on a more personal level.
Is he paying you personal attention, in front of others and one on one? If a boy singles you out, he's more interested in you than what's going on in the group. He may ask many questions to learn more about you and try and relate to your further. If he asks for your number, or is a friend that already has your number, and is calling or texting you often to find out what you're doing, to talk, or asking to meet up later, he's trying to keep tabs on you, and find ways to get more involved in your life.
If you're still unsure about whether or not he's flirting, talk to your friends about his behaviour, and see what they think. If you're sure it won't get back to him, you might want to consider asking his friends whether or not he's being more than friendly with you. Most importantly, go with your gut, and don't feel pressured to respond to his flirting with your own flirting if you're not comfortable with it.
If you think someone you're not interested is persistently flirting with you, you may want to let them know that you aren't interested, and make it clear to them that you're interested in them as more of a friend, or not at all. Be careful what you say, and how you say it so you don't upset them more than you have to.