Guy help pleasee!!!!!!?

Soo. I like this guy and we have been talking on facebook for about a month now and like he acts like he likes me most of the time, but sometimes I can't tell. He does winky faces ex ;) a lot and he does flirt like crazy. He walks me to cl sometimes.He is very sweet, genuine and attractive. He also wants me to hang out with him outside of school. But he is also close with my sister and pleanty of other girls. I don't know if he likes me or if he is just a nice guy.