Heeeeeelp!!!!!

[FULANITO]

Somebody please help me!!!
I purchased and mounted my tv-on-nav system with reverse camera, but I am stuck on the relay part!!!
What I would like to know is:
1.) Is there a particular type of relay I have to buy?
2.) Which ones and where are the wires that I have to connect into this relay besides the ones that are on the camera and on the video module harness?
3.) How do I tap into these wires, do I have to cut them?
4.) And finally where does the relay go connected into?

If anyone can help me, please do so. It will be deeply appreciated!!!
I've been stuck on this for about 3 days now if not more. Thanks to all in advance.