Okay...you could just kiss him, but I think that would take alto of the thrill away. And he wouldn't value you as much.
SOOOOOOOOOOO...I think the guy should initiate the first lip lock. LOL.
And yeah, shy shy shy awkward. My now ex, WAS THE MASTER of being shy and awkward, and he eventually got to the point where he wanted to kiss me enough..He leaned in and did it. And it was all that much more special

Anyways...my point is..if you re going to prom...I think you re probably gonna get some kisses by the end of the night (Idk for sure..Ive never been and never will get to go to prom..also thanks to my now ex. LOL).
But...if he really is unbelievably shy..I suppose you could kiss him on the cheek (closer to his mouth), and pull away really slowly. He should take it from there.