How can I talk to this guy?

So there is this guy at the mall, he works there, and he's really cute!! I've been wanting to say hello and tonight I finally did!! He seemed nice, he smiled and said hello back. I was all like, hey my friends wanted me to say hi, so hi. and of course I smiled and was all happy!! But I mean I kind of want to make another move in someway, but I don't know how. I'm also very very shy and I chicken out on a lot of things. I had the best opportunity to talk to him, he sat behind me and my friend while he was on his break, but I was too shy to say something. I just need some help and advice. :) thanks so much!!! :)