Well, you could make yourself dead sexy and irresistable. Go lift some weights or something
I'm in the midst of recovery myself. Hell, I'd even say I've completely recovered attitude wise but just need some experience. I had a horrible phase when I was like 13 where I was "the friend" to a few girls I was either insanely attracted to/in love with. I'll be 17 in three weeks, just to give you an idea of my age and stuff. I now make sure I only become friends with girls I am not attracted to. I think just in general I've improved my confidence and I think my personality has grown, and I'm understanding it a lot better, too. I no longer go to sleep thinking woe-is-me-and-my-lonliness quite like I did back then (not that I still don't have episodes now and then ).
How I try to avoid the friendzone is by not neccesarily being friendly. What I mean is, be friendly, but not like "hey, we should hang out some time" "i love you" or "your my best friend" friendly. Be nice, but don't be afriad to tease her a bit, too, and don't treat her like she is the queen of earth because she is hot. Hell, do the opposite, tease her a bit jokingly so she knows you don't think of her as the end all be all of everything. I think that was the thing I screwed up when I was younger. It's actually funny, and sad, how many good opportunities I had when I was younger that I never knew about but now realize I missed out on because once they got to know me a bit I was friendzoned. Also avoid the word friend being associated between the two of you. I never refer to a girl I'm attracted to as my friend, just to avoid brand association :P.
I've found that just general stuff you should do in any conversation is helpful, like having good eye contact and body language (i.e. some smiling, facing the person, ect) make conversations a bit more fun and less anxious.
Do you have really great hobbies you love? I think this has helped me a lot. I don't care if girls like me or not that much these days, because I'm not exactly looking to get married anytime soon, and even if I do wish I had a girlfriend or a FwB or something, I don't mind because I still have ways to occupy my time just as well.
I still have some work to do, but at least I now have some prospects to think about. Rather than getting friendzoned, girls actually like me now and flirt a bit (or at least I notice it more when it actually happens). I still need to actually get some experience, and I'm afraid I may be somewhat avoidant of intamacy, but I havn't been friendzoned by anyone I was attracted to for almost two years now, and thats what counts.