This articles explains how to make a wire up RJ45 patch cables.
Straight Cables
As the name suggests, a straight cable is wired pin 1 to 1, 2 to 2, 3 to 3 etc. These are the most common cables, used between computers and hubs.
Crossover Cables
This cable is similar to a straight cable, but with pins 1 and 3 crossed, and pins 2 and 6 crossed. This cable can be used to link 2 computers without a hub.
