The How2Become guides are generally bullshit afaik. They just compile obvious, freely available information ripped from websites such as this or actual advice given by the organisations in question.
Go to a bookstore, you will find plenty of practice / self-help books dealing with aptitude tests.
DONT use these AS revision! These are just GENERAL stuff "LIKE" the test. My friend (nice guy) studied on these HARDCORE and found that the test themselves were laid out different, written different, and far more confusing then these simple questions that these guides offer.
For the records... I did'nt use anything but GCSE Algebra/Fractions revision guides. And qualified for "Aerial Erector" easily.
Survival Equipment Fitter
Aptitude Test - PASSED!
Selection Interview - PASSED!
Medical - PASSED!
Pre Fitness Test - PASSED!
Final Interview - January 2nd!
Halton - January 23rd!
Cosford - Febuary!