You don't have to do anything special. Stand on toes or stand on staircase higher than him. It's all right. :)
Even if it is a little inconvenient it is not that big deal. He can do it even if you don't help him. That kiss is worth it. We guys feel amazing when we kiss and are kissed. And little inconvenience will be forgotten easily.
I'm 6'5"ish almost 6'6". My girlfriend isn't short but there is a little bit of awkwardness with the kissing initially. She has on numerous occasions worn high heels that brought her up a good 3-4 inches. It helped. Also steps are good. Occasionally in the kitchen she'll use a step-stool that brings us almost eye to eye.
Wear heels. Wrap your arms around his neck and tilt your head back and look into his eyes. He can easily take a wider stance and dent a little to kiss you. Also you can easily kiss while siting next to each other, and latter on when you two are more comfortable he can pick you up and hold and and kiss you. =D It works. Don't worry about it.
There are other ways, I'm tall for my height and there are ways he can kiss you on the neck. By cuddling, laying down, or by lowering his head. It how he can find a way to kiss not just by asking you where he wants to kiss.