I got a grade 8 in my year 10 mock, but no one really took them seriously. I'll be honest, I didn't as revise much for maths as I did for my other subjects as it came naturally to me, and I had a great teacher- definitely use all the resources your teachers give you! In terms of revision I went over topics I didn't know and I do think practise questions (not papers, because you know you can tackle the easy ones, so they are a waste of time imo) are the best way to revise but only if you know all the content you are being questioned on. Workbooks are also great- I had the edexcel workbook (light blue) and the CGP practice questions workbook which I found really good. As it gets nearer to the exams, I would strongly recommend printing off big booklets of practice questions or getting them from teachers as they usually have them lying around, as they are so helpful. As for tackling the more wordy questions, I would recommend looking over the topic the question is on whether that is in a revision guide or online, the maths websites you mentioned were the ones I also used, no others spring to mind, and making sure you really understand what the question is asking you before you give it a go, and do questions that you have access to mark schemes, as they usually take you through the working out in the answer. I hoped I've answered everything!