You either got it or not!
I agree with Lon More... You canNOT prepare yourself for FEAST tests! The most you can do is prepare your health for the medical if you get to that stage by keeping fit. FEAST tests are there to see if you as an applicant has what it takes to be an ATCO; don't try cheating the system by asking what the FEAST contains as you'll realise your mistake once you start training - if you get there!
I've started my Basic Training in Lux and the failure rate is 50%. Reason... students don't have the aptitude for ATC. So if you want to be sure you'll succeed all the way through, take my advice - just have a good night's rest before the tests. You cannot prepare yourself. Don't bother gathering info beforehand; you may end up being bitterly disappointed in the future!
Good luck for your Phase 01 FEAST.