I think the most important thing is to be yourself, don't lead him, or anyone, down a false road, that's cruel, and a waste of time.
And don't be afraid to take the intiative! Some of us guys, myself included, and quite timid

when it comes to these things, but when SHE makes the first move, than its much easier, and breaks tension wonderfully.
To show that you have the guts to ask a guy, rather the other way around, is very impressive. Don't underestimate the power of the message this demostrates, which is one of both independence, and of..err..kindness?
It may not sound major, but this makes a big impression, and if your interested, go for it. He's probably trying to get the courage to ask you.
NOTE TO ALL:
Being nervous means you care. Caring is good, it means you hope the outcome will be postive. Being nervous is a good thing!
Hopefully that wasn't too sentimental.