You should watch my free lectures on planning and operational variances. (The lectures are a complete free course for Paper F5 and cover everything needed to be able to pass the exam well – I cannot type them all out here 🙂 )
However, do not simply learn formulae! Only 50% of the exam involves calculations – the rest of the exam is checking that you understand what you are doing. Even in the calculation questions, the examiner deliberately tries to phrase them in ways that make sure you understand and are not just learning rules and formulae.