after just doing mine, i think flashcards for learning terms - which are really important in the exam, posters/fun stuff like mindmaps for case studies which you should try to make as you learn them and look over frequently (flashcards for case studies are really good) and past papers! i personally think that the exam technique is quite tricky in psychology so past papers are really good for practicing it.
(btw you can find flashcards for psychology on quizlet if you don't want to make them)
- i did edexcel and the textbook was super detailed for no reason so i didn't use it very much which ended up being fine but you might be doing a different board