First thing to do is remove the seat to gain access to the battery:

2nd: Get a waterproof fuse holder and fit a 10amp fuse

3rd: Strip the ends off of some twin core cable and fit a ring terminal to each wire for the battery screw to go through.

4th: Cut through the power wire and fit in the waterproof fuse holder using heat shrink terminals. Remember to heat these with a lighter to make waterproof.

5th: Cut the wire where you want to mount the on/off switch:
6th: Cut another piece of twin core to go from the 2nd terminal on the on/off switch and fit a spade terminal. This is the power feed for the lighter. The other wire goes is negative and is crimped with the negative wire from the battery.

7th: Fit your wires to the switch. Power in to number 1. Power out to number 2. Negative from the socket and the battery to number 3.

8th: This is where I drilled the hole for my switch. Just below the seat between the frame and fairing. If you decide to use this place be careful of the wiring loom and the battery. Drilling through either of these will cause a nasty mess.

9th: Connect your ring terminals to the battery and test with a charger to your satnav/phone or what ever.
I forgot to get a pic of the switch in place so you will have to use you imagination. Hope this will help someone out there at some point.