I always revise for the skills exams in the same way, and I've so far managed an A in AS Skills and a B in A2 Skills.
I just write everything out in REALLY simple terms. For example, I'd write 3 two word bullet points on the location of my fieldwork, same with my aims etc, so I can remember them easily; I know I can stretch it all out properly in the exam.
For the actual skills part, I do the same. I write three bullet points on what's good and bad for each type of graph etc, and for the stats I simplify it as much as I can too, by writing things like "large standard deviation - numbers spread around the mean".
I know it seems simple but it's worked for me so far, and if anyone wants me to scan my notes etc, feel free to ask!
(Obviously my fieldwork might not be applicable for most people, but we did ours based on Bradshaw's Model, and how a river's variables change with distance from the source, so if you needed that too, you could adapt it? The risks etc are the same)