Michael
Don't be sucked into thinking that paying for powered flying lessons will give you any advantage - it won't. The selection process is geared towards finding your aptitude, not your current level of skill. If you are not already a good player of fast-action ball games, or their equivalent on games consoles, then practice your hand-eye-brain co-ordination. Practice your mental maths skills - and work on your life skills - the Duke of Edinburgh programme is ideal.
If you can, join the Air Training Corps and get on a free Gliding Scholarship course. Google for the organisations that provide flying scholarships and apply for all of them...
Good Luck.