This is a quick guide for LAN cable construction.
The most common standards are T568A and T568B with the second being of the most use.
Both use the same electrical connections but different colors as seen in the following figure.
In order to make a straight cable, as one to connect a PC to a Hub, use the same color connections on both ends following either standard.
In order to make a crossover cable, as one to connect two PCs, use T568A in one end and T568B in the other.
The Pin numbering is shown below
