Go to:
http://www.easa.eu.int/home/regul_en.html
Download:
Regulations – Part 145 - and also Acceptable Means of Compliance & Guidance Material to Part 145
A read through all these (how much?) will consist of a Guide for what to do.
When you wake up, you should understand some of the complexities of the hoops they want you to go through.
When you have some further understanding, and want to go further still, ask the CAA for info on setting-up.
As Spanners says, there is a cost to Licensing, and more for setting up your own Company - There is costs for anything in UK - but I believe those particular can be worth it.
Best of luck!
If you want any more PM me.
Rigga