AQA A Level Chemistry Paper 3

Hi, does anyone have any tips on how to prepare for paper 3 in AQA A level chem?
It's on everything and seems really unpredictable, and I heard its this paper that really separates the A* students.

About 20-30% of the marks on this paper are on practical skills. So far they have focussed quite heavily on the AQA required practicals, so I would make sure you know them well.

AQA required practical
1. Making a standard soln and titration- not so many q's on this, more of an AS topic
2. Hess' law/calorimetry- this has come up
3. Rate of reaction- disappearing cross- not so much in paper 3, as examined in other papers
4. Tests for halide ions , group 2 ions etc - not so much in paper 3 as examined in other papers
5. a Oxidation of an alcohol to an aldehyde- this has come up a lot
5b. Dehydration of alcohol to alkene- this has come up a lot
6. Test tube tests for organic- not come up much in paper 3
7a Rates- collect H2 - not so much
b. Rates - Iodine clock - has come up a lot in paper 3
8. EMF of electrochemical cell- hasn't come up
9. Titration using pH meter- hasn't come up
10. Apspirin prep- has come up loads- melting point determination, vacuum filtration, recrystalisation- lots of q's in paper 3
10b. Making an ester- has come up a lot- use of sep funnel to wash organic liquids, how to dry them
11. Thin layer chromatography- not on paper 3 much