Things to think about before applying to graduate school:
It seems simple... but the first thing you should ask yourself is whether or not going to graduate school will even help you achieve your professional goals. A lot of folks assume that this is the case, but quite often, graduate school ends up having more financial consequences than professional benefits. So do some research into how people successful in your field of interest got there. It might just be that internships or entry-level positions end up getting the job done better than another two-six years in the classroom.
Ask people already in the program you are interested in about their experiences. Asking people in your specific program of interest is important, to often people think just talking to any random graduate school will help them out. But oftentimes, a masters student won't be able to tell you how to get into a doctoral program. A political science student probably won't be able to tell you how to apply to a psychology program and a medical student probably can't help you get into law school.
When you do talk to people (especially potential writers of letters of recommendation) be clear about where you are in the process of thinking about graduate school. If you aren't sure if you are ready to apply to graduate school, make that clear. If you talk to a bunch of people, and they dedicate a lot of time to trying to help you get your application together and then you don't follow through, when you actually are ready to apply they may not be so willing to help you out.
If you are applying to doctoral programs, ask yourself if you have existing relationships with faculty who can write letters of recommendation for you. If you are a couple of years out of school and have just lost contact with former mentors and professors, that's ok, there is probably some leeway to be had. But if you are a senior in undergrad, or just recently out of college and you don't have any faculty who would be willing to write you a letter of recommendation... that might just be a bad sign (lol... remember this is just my personal opinion).
When applying to doctoral programs, don't get so caught up in the department that you ignore the climate of the campus itself. Make sure there are resources and people present that will help you live in a way thats healthy and vibrant (to the extent that, that is possible in graduate school).
more to come...
p.s. check out my post on finishing the chicago marathon