Is he persuing a relationship with you? Has he asked you out? Has he complimented you on your looks? Has he made excuses to touch you or hold your hand? Has he teased you? Those are some good indications. Don't sweat it around him. Be yourself and enjoy your time with him. If you spend enough time with him, time with tell if he really likes you or not.
Honestly, the best way is to just ask him out. Sometimes it works, sometimes it doesn't, but at least you know. And so does he, and that knowledge can be a pretty powerful thing.
He likes you for sure
Kiss them and see what they do
== == == ==
When he is sure he likes her.
To be sure whether or not a guy likes you, you could always just ask. If not, have a conversation with him, ask him if he wants to hang out with you.
the only way to be really sure is to ask him
Not sure how you expect someone to magically know something.
ask him
Make sure you both like each other. If one of you don't like the other then it could work out badly. But if you are really sure that this guy likes you and your ready to commit, go for it!
Ask him.
He tells you, frequently and with enthusiasm.
Have friend find out if he likes you. If so, just ask.