Welcome to the site. First off, well done! I see that you have passed your PRMC, so do you have a start date for RT yet?
I expect that you're aware that Foundation is extremely hard and while you have to keep your fitness up, it's also important to start learning other skills, such as dhobying and ironing. Getting to grips with these two before you pitch up at CTC will save you one precious element and that is sleep!