I hope that this is the right place to put this, I'm new to this site. 

So a few months ago I found out about smegma and how you should clean your penis a lot more than I thought you did. I'm 15 and thinking about it I've had this problem for a few years now. My problem is this: There is this weird crust on my foreskin, not underneath but actually on it. Originally I thought it was smegma, and I still think it is, but I just don't know a way of getting rid of this crust. The thing that troubles me is the fact that there is quite a lot of it. I'm concerned that it just won't ever go and will never stop spreading. Also I can't retract my foreskin fully back but enough so I can know that this crust on my foreskin is on it not underneath. But I'm working on retracting my foreskin back. 

I'd really appreciate any suggestions on what to do. And thanks in advance.