Advice for playing a successful Jarvan IV

Hi RofL, I am trying to learn Jarvan because I like the way he can control a fight and his mobility with E>Q combo. If any long-time Jarvan players could help me with tips and tricks I would really appreciate it.

A couple of things to mention:

I am really most comfortable in the jungle or solo top. It seems Jarvan has a painfully slow early jungle which is bad with the jungle changes (though I remember seeing some beast jungle jarvan a couple months back in a tourney)

Solo top, I cannot figure out how to sustain properly and get harassed out of the lane. I think I just need to get better at farming with Q.

Thanks in advance RofL