Ok, I think I can help you out since I have half of your classes. For Psychology, what you need to master in order to pass the class with flying colours is your memorization skills as well as your critical thinking. You'll need to memorize a TON of studies as well as different approaches, technologies (for biological) and more. If you want to soften the load, you need to find studies that overlap a lot. For example, you want a study that can cover sociocultural aspects as well as biological. Also, when you do your SAQs and ERQs, make sure that you make your thesis/statement clear and that you take the time to well explain how the study links back to what you were saying. The connections you make are more important than the study used.
Once again, biology requires quite a bit of memorization so if you can, study the terms in advance so that you can grasp certain concepts like cycles more easily when lessons come. It'll also help a lot if you practice biology questions straight from the question bank. That way, you have a clue about how the subjects are often brought up in questions as well as the type of answers that each command term in biology requires.
For Math SL, it would be of great use to look over Grade 11 functions, Grade 12 Functions and Grade 12 Calculus since these curriculums basically comprised of these curriculums. Plus, there are a lot more good and practical ressources available for these courses than there are for Math SL. That being said, so that you can get used to the style of IB math questions, refer to a question bank or check out ressources like past papers or the Oxford Math manual since that's the most extensive guide.
As for LAL A and Lit A in general, make sure that while you're reading the works to effectively annotate. Write down important themes, motifs, characters traits/arcs, etc. so that when you have to write your essays and commentaries, you have plenty of notes that are readily available. You also save yourself time since you won't have to read the entire work again just to remember what exactly happened. Also, plan your essays in advance so that you have all the time in the world to brainstorm and give yourself the most interesting, most concise and overall best topic available.
Hope this was useful and enjoy your first year of the program! Don't forget to relax and take it easy :)