Now that I have received my statistics score, I can safely answer this question.
What I did was made sure that I memorized the variance, standard deviation, z-score, r, slope and y-intercept equations. I already knew how to do probabilities, so that wasn't an issue for me. When I got into the test area, the very first thing I did was write the above equations on one of the scratch papers. This way, I didn't have to worry about trying to remember the equation later in the test after my brain had been thinking about something else.
For test prep materials, I used IC and the Complete Idiot's Guide to Statistics. I also had the CliffsNotes book on Statistics, but I didn't like it and I didn't use it much. I studied for exactly one week. My test center only tests on Tuesdays, so I am scheduling one test per week.
After 20 days of waiting, my Principles of Statistics score arrived today....
78!