how to start a conversation with somebody?

Well, first of all, you just need to act normally. And that's actually way easier than you think. You'll be creating all this "on your part" perceived awkwardness because you know that you like him, but he won't notice a thing since he doesn't realise that you like him. It took me quite a while to realise this; the awkwardness really only exists on your side. So, just do your best to realise this, and it will go a long way to diminishing any social anxiety.

Secondly, since you have so much confidence that he likes you, then anything you do, even if it is extremely awkward, he will love. Think about it: does anything he does make you think he's weird? No. I've never thought anything one of my crushes or something someone else has done to be weird, and in the very rare circumstances, I'm pretty sure I've completely forgotten about them.

But this is some general advice.

How about you give us some actual situational detail, as in when and where you have the opportunity to chat with me, so we can give you some more specific advice?

 

Thank you! That is what I tell people all the time and it's true much of the time =)

If you're pretty sure he likes you, he probably wouldn't mind anything that you do to talk to him... within reason

 

I think it's best if you tell him when you are alone with him or something, face to face because you owe it to yourself and to him that respect. And if the worst case scenario happens, not everyone will know.

There are plenty of ways to do it I guess. For me I just told the person I liked face to face, it ended in a no but there are many other ways. If you are really anxious, you could write a letter for him and make him read it in front of you and tell you what he thinks. You can write for him a poem. Take him out to a movie and then tell him there. etc...

There are many ways to do it.

I sincerely hope that love will be fair to you.

Good luck.