Hey,
There realy isn't much you can or have to do to prepare yourself for this tests, seriously....
All you can and have to do is try to be as rested and calm as possible.
You will be faced with some reaction and multitasking tests, some test regarding you spatial awareness. But it honestly wouldn't help you to tell you all about these tests in detail since it will not help you in any way.
Every test you will have to do is well explained and you will get some practice runs before you do every different part of the test.
One thing I can say you that will help you relax from time to time during one of the more difficult exercices.
You will have to do an exercise where you have to sort items in different categories. you only get about 2 or 3 seconds to do so before a new item appears. from time to time it will say on your screen "new sort code", this only goes away when you click.... don't just click this away at once but take this time to take a breath for a few seconds, then click on it and start working on the exercise again. It's those things that can help you pass somethimes.
Some other basic things:
-you will see some test involving headings and distances, but I would guess you know the basic headings (it's all written down in the test as well, everything you need is in there)
-you will be tested on your english understanding
-you will be tested on understanding and remembering accurately different large numbers
-you will get more cubes to solve
-you will get a strip display exercise but since this exercise is not exactly following atc rules there is nothing I can tell you about this, this exercise is as well meant to check if you can learn things in a (short) amount of time and apply them
-you will be tested on reaction time with a very basic exercise
As well whenever you feel like you are ******* it all up, just keep on fighting, never give up. Giving up is an attitude you can't permit in atc and sometimes they will be face you with situations that you just can't handle perfectly, these are the times that you have to show you keep fighting for it, set your priorities and make the best out of it.
Anyway, good luck and keep it up, just be as calm and well rested as you can.