Not a stupid question at all.. The only type of stupid question is "where can I download so and so game".
Are you wanting to make one from scratch or modify a normal patch cable?..
I hope this link helps.. It has pictures.. Tyler like picture.. Tyler no like read.. Bahah just kidding buddy
OLD pal.
Quick diagram on the wires that are modified.
http://www.perfectdrivers.com/howto/crossover.html