I also did Edexcel A levels and apart from Unit 3 and Unit 6 I got full UMS in all papers(590/600) so I guess I can give you few tips.
1,Use the edexcel endorsed textbook keith Pledger
2,Read the textbook thouroughly atleast 3 times after you understand it fully.
3,Then research more on each topic and make notes(for example if you are studying about photoelectric effect search about it more on wiki, google, etc and deepen your understanding)
4, At the end of the week before you go to bed keep thinking about what you studied the whole week and apply it(design your own solar cell LOL !That's what I did though)
5, Last but not least try to develop a interest in physics !
Best of Luck !!!