I will likely be taking a year off. Depending on what you will be doing (working I presume), some reading and polishing of essays wouldn't hurt. But, to be honest, the big thing to work on for many applicants is their GRE score. I had scores that were good for most disciplines, but mediocre to sub par for philosophy the first time around. Thus, I will be spending a large amount of time studying for the GRE. Did you apply your first time around? If you didn't, perhaps familiarize yourself better with what sort of applicants are getting accepted to the programs to which you hope to be apply. If you did (like me), take a close look at where admission committees were weeding you out. That is, explain to the programs to which you were denied that you plan to ask programs that you were rejected by specifically why they did not find you to be a competitive applicant.