Hello and welcome to the forums.
As I'm sure you'll be aware there are a number of threads relating to the Etihad Cadet Pilot Scheme. May I suggest you use the websites search function to find out any information you need. You may not be aware that Etihad aren't too keen for people wishing to sit the assessments this year talking about past ways of testing. Apparently these forums are monitored by those who work at the airline so it's best to be a bit tactful about what you say.
It's common sense really, all I can suggest to you is that you revise your physics and maths knowledge very well. It might be worth while reading up on Etihad, it's history and they country it represents. I can't suggest how you're best preparing as different people have different learning styles.
Good Luck, S88
