I am not sure if there is such a thing, however I highly recommend knowing the most common laws that relates to Penetration Testing.
One way of obtaining a "cheat sheet", could be doing the SANS 560 course (just read the books), and then create your own notes from that, about what you feel is most appropriate to have with you.
I also recommend notes about the laws in particular, terminology, ethics, planning and performing a pentest (the non-technical part with NDA's and permission memo's). Last but not least, commands. (If you can't remember the proper syntax, write them down.)
There's of course technical questions too, both practical and theoretical. If you don't know the theory behind password algorithms, protocol encryption, and much more then you would have to focus on these as well.
The best way for you to find out what you need to focus on, if you already have a good base knowledge within information security, is to do one of the practice exams, which you can do from home. I did that and realised I had to know, a lot more about the laws in various countries, not covering the ones I've lived in at all.
I'm an InterN0T'er