Self studied F/P myself in SA and ran out of time the first time I sat it. Sorry to say it but it's practice practice practice. There is a lot to be said for question recognition.
Know your graphs, they can waste a lot of time, and have a sharp pencil.
Try and work out a structured method for working out curtain types of question. Air rang is a good one for this. That way when you get that sort of question you can just plug straight through.
And the last thing, I know it's so obvious but still gets me all the time. RTFQ!! The amount of time I've wasted trying to get the number to work in a PSR question only to realise I've been working in Kms not Kts.
Best of luck.