If you purchased an OEM trailer harness then this article really isn't any use to you as it will be plug n play. But for those that have purchased a generic 7-PIN harness from you local auto store here is some easy reference guide. 

For the job you will need a 7-PIN trailer connector (I know there are others, just use what you need I suppose), 1 meter of trailer cable, heatshrink, electrical tape and of course zip ties. 

Locate your OEM connector 

This is usually in the boot (Trunk) on the left hand side tail light access panel. The OEM connector will most probably be white.

Cut the OEM connector off and apply the following wiring scheme: 

Using the above wiring scheme connect the harness and OEM wires. Tis best to do it right the first time so spend a few dollars more on some heatshrink.

As a 'Just in case', the blue wire (Trailer Brakes)was left out and capped so it could be accessed later on without the need to unwrap all the work we just did.