Thank you for the opportunity to help you with your question!
You should prepare yourself by having a study plan and know whatever test you are preparing for-A work plan will guide you on how to study and what to study for.
Know your revision tips- this can be by organizing your notes and being active in your revision. Stay motivated and look for revision materials to help you recall on what you have read.
You should also know how to deal with specific questions-Different tests have varying questions and so during your preparation, you should familiarize with them ;for instance essays, short questions, multiple choices or even problem solving
Please let me know if you need any clarification. I'm always happy to answer your questions.