Hey, for starters you could refer to
https://www.thecorporatelawacademy.com/forum/threads/the-best-sjt-advice-on-the-forum.4350/ which is just a compilation of how to approach these tests in general.
For the CAPP specifically, I have just one piece of advice,
be honest because there is no particular skill that they value. For example, if you get a question that asks you if you like working on innovative stuff or the routine stuff, naturally you will be tempted to show your fascination for innovative work (99% of people would) but that isn't always the correct answer and if everyone likes working on innovative deals then they'd run out of people to work on the routine matters which is equally important even though it might be less intellectually stimulating.
The CAPP test will make it look like it's a lucky draw but I think there is a real sophistication to the test which is impossible for us to know of. I am 100% convinced that firms like
Linklaters will not make the process as arbitrary as we may feel it is.