What modules are you already doing for regular AS maths? It depends on a) module prerequisites (for instance, FP2 and 3 are completely independent but both reliant on 1) and b) specific requirements in terms of the number of pure and applied modules you need to do for each stage.
However, I did Edexcel so I'm not sure how these specific requirements are for AQA. The principle will be the same, but details should be available on the official course overview documents.