If you want to join the "Forces" then the first thing you need to do is go to your local Armed Forces Careers Office (AFCO) and ask for advice. They will look at your qualifications and be able to point you in the right direction. If you would like to join the RAF, there are 3 routes depending on your academic ability, personality/manner etc and age. Airman, Non-Commissioned Aircrew (NCA) and Commissioned Officer.
If you decide to go ahead for airman then you undertake aptitude tests for ground trades such as aircraft technician. If you are suitable for NCA or officer, then, is you pass a filter interview at the AFCO you will be referred to the Officer and Aircrew Selection Centre at RAFC Cranwell, where amongst other things such as interview and team tests, you will get to undertake about 6 hours worth of aptitudes to test your suitability for your branch choice. You can't go with a "blank book" you must have chosen a branch or more and actually know about it.
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