Two months and you seriously haven't kissed her? Are you kidding? Why has she stayed with a boy who doesn't seem to have any want to be with her, who can't even kiss her.
Seriously, just go for it. Before she breaks up with you. She can be your test girl! Where you get all your experience!
The most painless and easy way in my opinion is when you're hanging out, sitting on the couch together or whatever. DON'T DO THIS AS THE MOVIES OR WHEN YOU'RE OUT. When you're hanging out, just put your arm around her first.
If you can't even do this just do the dumb yawn thing, and then you can say something like "Yeah, I'm smooth aren't I?" and you'll all have a big laugh that your can cherish forever, and you can think in your head "WOW! My first girl touch! Woopie!"
Next, after you get all comfortable and you've managed to get your boner to go away, just say something similar to "Hey Donna, can I kiss you?"
It's dumb, it's pathetic, and it's silly, but it'll work.
No doubt she will say "Oh yes I would love to kiss you Truman!" or something along those lines, but more likely just a "Sure."
If you need any tips on how to kiss go on google and look it up, seriously. Much advice can be found on google. But what I suggest mostly is going to the Relatonship Crew For any more needed tips and tricks.
Good luck sir, and don't fuck up or else it may ruin your entire life because you'll be unable to ever kiss a girl.
Give Vincoid a PM, he's a VERY wise man.