I did Air law and Human performance on the same day, then 2 weeks later I did my Met. Aircraft general came next shortly followed by the Performance and planning. I did my Nav exam just after Christmas and before I had done any navigation. I took the RT written in January. I will be booking in to sit the RT spoken exam very soon and the way things are going I guess I will have passed that before I solo as well. I found them all easy and I never picked up a book for the human performance exam.
Good luck.