What do you do if you want to take your friendship to the next level?

Hmmm. This is a tough one. The problem I've seen happen is that if too close, the other person may give the excuse that 'You feel like too much of a brother/sister/best friend and I don't know if I could ever see you that way...' so my best advice would be to go on outings where the two of you can become closer or talk about things. This would work best with things you are both interested in, such as a movie or some other fun activity, like minigolfing (if you find that fun C:) or going to an amusement park. To get them to think of you fondly enough to commit to a relationship, build happy experiences. And definitely be yourself - nothing could be worse for a relationship. Good luck!!