Ugh, you like a friend? My condolences.
LoL - seriously, though: in my AFC days I actually had a few girls who were friends that I was thisclose to screwing... but then I ruined it by either verbally expressing how I felt or having the opportunity to make the move but not taking it at the right time.
Here's a trick I did one time, only it wasn't a trick but what was actually happening. During my sophomore year in college I was on a dating roll one week where I had gone out with 3 girls in 4 days. I was visiting my one of my girl friends in her dorm room, and mentioned to her that I had gone on this successful string of dates and was just having fun going out with new people that I hadn't even considered before.
Then, I looked at her and said, in a very nonchalant way: "Hey, you know what? We should go out on a date, it would probably be kind of fun!"
She paused for about 5 seconds, then said... "yeah, sure, we should do something sometime!" I ended up taking her out the next week, and sure enough it was fun! (A couple years later we almost ended up hooking up as well, right before I c-blocked myself... but that's a whole 'nother story.)
It really is as simple as asking sometime. Remember: girls LIKE feeling desired AND like having fun. You don't have to go into some big speech about how you like her and think you two might have a future together - just make it a thing where you're curious about what MIGHT happen on a date with you and her, and see if she's down for some fun!