any tips for ocr short course gcse rs?

My best advice for you would be doing past papers as much as possible (especially for maths and sciences), they will often use similar questions that will probably appear on your actual GCSE's. If you can't do practice questions (e.g you don't know the content) I would go through the textbook, read through the notes but write questions as you read through it. This is for you to answer once you have read the section. Its a quick way to generally know the content and build off using past papers. Flashcards can be very helpful (quotes for english and key words for languages) however don't bother making new ones at this point at time, unless its small notes that you struggle to remember.
I hope you do well in your GCSE's