For subjects like science and maths I recommend just revising and practicing different questions, it’s annoying but that’s the only way. You still have some time but if you really want to get those grades then you will probably need to spend a LOT of time over Easter revising (I revised around 6 hours a day nearly everyday over Easter and got all 8s and 9s) - also for English lit/Lang and history all you can do is revise content then apply it to questions, get your teachers to mark them and make sure you do everything under timed conditions and apply the feedback they give you!!