Let's Make Robots!

NEED HELP! with my motor controller

Hello guys. I'm creating a RF controlled 2.5kg sumo bot. I'm a mechanical engg. student and so don't have much knowledge in electronics.

Basically I need to create a 10Amp motor driver for driving 2 12V dc motors,10A each using relays.
Buttons on remote control:

2           3

1-Move Forward
2-Rotate Anticlockwise
3-Rotate Clockwise

I'm planning to use these schematics for radio controlling


My Questions are:
Can anyone please create a schematic showing how to use relays to control motors from the o/p of the decoder?
Wil the circuit explode if more than one button is pressed?