How to play top, adc, and jungle?

Okay, so I recently got to level 30 basically as a support and mid main. However, I'm not really familiar with other roles, and I kind of want to be, as in ranked, I'll probably have to play one of them. I'm not really sure how to top, but I do have a few Top champs (irelia, shyvana, and kennen) though I'm not really used to the melee playstyle. I have three adcs (miss fortune, ashe, and sivir) however, every time I play any of them I seem to have trouble. And as for jungling, I don't really know how to at all, which sucks since I've had to duo top in situations that support or mid were taken. Do you have any tips for playing any of these role? I'd appreciate it since I do want to play ranked, but I don't want to start without diversifying my knowledge of all the roles. I'm not that great at melee champs (mainly because my most played champs are lux, morgana, Sona and lulu) and I usually adapt to the cc playstyle. And if you have suggestions, who's a good jungler that's easy to learn with? I'd like to know before s5 starts. Thanks for your help :)