I took a year off, almost 2, and here are my tips:
1. many schools will ask for recent rec letters(i.e. from someone who dealt with you after you graduated) so make sure you're involved in something (volunteer, work, classes) so that you can get that new rec letter.
2. many schools will ask on their secondaries, and also in their interviews, what you've been doing with your time off and/or why you took the time off. have a good answer (you wanted to improve your app, family emergency, took MCAT too late, etc) and not just, "well, i wanted to relax a little." (even though this is personally a great benefit to taking a little time off--do it while you still can!!--it should not be your ONLY reason.)
3. Some schools will specifically ask you on their secondaries, "what have you been doing in your time off to account for FULL-TIME involvement," which means, what work/volunteering/classes/other things have you taken on to account for 30+ hours of your week. Don't sit around and waste that time; you need to be productive in some way or another, even if it's not specifically towards something clinical. Maybe you're working on a project with your church or doing Peace Corps; whatever it is, be productive.
4. YOUR MCAT! Remember that your MCAT scores will only stay good for about 2-3 years at a lot of schools. In the event that you do not get in the first time you apply, you may need them to be good for a second year when you apply again. If you have already taken the MCAT, (I took mine the summer after graduation) I suggest you go ahead and apply to schools ASAP. If you get in and you still need more time off, you could potentially defer your acceptance another year; you just wanna make sure you get in before your MCAT score expires, because nobody wants to have to take that test again!
4. remember your timelines. the application process is a very long one; remember to plan out your next two years carefully to allow you to start the process the summer BEFORE the summer prior to your expected entry to med school. during the summer that you apply, make sure you have ample time to fill out lots of secondaries, because you will want to apply broadly, and secondaries are very time-consuming (that summer, applying to med school will feel like a full-time job), so plan to keep your plate light that summer. If there are any big trips you'd like to take out of the country, take them prior to that summer, if possible (or during the summer before you enter med school), so they don't conflict with the application process.
5. Throughout the application cycle, make sure you always have access to e-mail. You should be able to check your e-mail every day, even if you don't have cell phone access, because almost all schools these days do the majority of their communication with you via e-mail. Responding quickly is vital to keeping the process moving forward.
and finally...
6. During your time off, do stuff you can't do while you're a full-time student/employee/parent, etc. This is your chance to take that long backpacking or road trip you always wanted to take. Do it now before med school, and residency, and eventually, parenting happen in your life. This may be your last big chance to take extended trips before you retire! Don't miss out! Even if you can't find a job or don't plan on taking classes, set goals for yourself during this time, so you have something to work towards; it'll keep you from getting lazy/unmotivated during a time where your life seems to be on hold.
Well, I hope this helped. Taking time off is beginning to lose the stigma it once had, as it becomes increasingly more common amongst applicants to med school. It doesn't hurt your chances in any significant/noticeable way, from my experience (probably due in part to the fact that I worked a few part-time jobs and volunteer gigs to stay involved "full-time" throughout my year off). But at the same time, I also saved up money to go on some great trips around the world this year too, and it was a lot of fun to just relax for once. I wish you the best; good luck!