Just a couple of points of advice on contact:

1) Never be violent. No relationship is improved ir strengthened by violence. If you can, don't even raise your voice. Horseplay is fine so long as it's consensual, but never go in trying intentionally to hurt them out of anger.

2) Enjoy hanging out and spending time with them for their own sake. Nobody wants to feel like you only care about them as a sex object. If you wouldn't want to hang with them without fucking them, don't fuck 'em.

3) Give them the space and ability to say no if they don't want to. They know their body better than you at any age. If they wanna stop, don't pressure them. That sense of control and autonomy is invaluable, and it greatly hurts when it's violated.