I have posted my tips in a duffers guid on my blog:
https://www.designflux.org/blog/?p=135
I used the Kaplan and Princeton books to learn the methods and the GMAT review to come to know the questions. I used Manhattan GMAT for its great free online resources and I also signed up to its online practice exams which I found to be the best in terms of diagnostics.
I also used the GMAT prep software's 2 prep tests in the final days before the exam to get grounded in the GMAT style rather than its simulated style via Kaplan or Manhattan.
My best find was definately the 'Variables In answer Choices - VIC' method. Had struggled to do these with algebra previously and the picking numbers method really worked well. Both Kaplan and Manhattan have good guidance on this.
Thanks again!
![Image](https://www.postimage.org/aV9YNM0.jpg)
I have added my excel file notes on question types - its real rough but might be useful!