I only took maths out of the ones you're doing, but, the most important thing with maths is practice. It's the only way you'll get good at it, and unlike other subjects, you cant cram at the last moment.
Also, get your hands on a good revision guide. It'll make things so so much easier, and always try to do questions that you think look too hard or out of your league. It's the best practice you can get and it'll help your confidence when you get them right
Good luck!