Laura at 11D posts a very solid list of recommendations for people embarking on post-high school education.  

• Don't get an AA degree anywhere but at a super cheap community college. Go to a local community college, live at home, and get a part time job.
• Don't take out anymore than $15,000 in loans. 
• Try your damnest to get done in four years. 
• Don't choose a school based on the college atmosphere. 
• Never get a Masters Degree in anything, except if it is guarenteed to increase your salary. 
• Never get a PhD in anything.
• Never get any degree in a profession that doesn't require a degree. (You don't need an AA degree in party planning, for example.)
• I would like to tell people to avoid schools where the professors don't actually teach any courses, but it's hard to find positive examples anymore.
  

I'd add just a few things:

1.  Work for a year before you go to college; you'll get much more out of the experience, and you won't need to borrow as much

2. Don't major in English or history.  It's getting hard to overcome a poor major choice by going to grad school.  (I say this as someone who . . . majored in English and then overcame a poor major choice by going to grad school.)

3. Don't enroll in a master's program unless you observe a lot of that program's graduates are working in places you'd like to work, or you hear from someone in the field and geographic location that you want to work in that they hire out of that school.  Many programs exaggerate the job-getting powers of their degree; they'll parade graduates who got super lucky, or happened to be the son of the owner of the firm, without letting you know how unusual these cases are.

4. Do not, under any circumstances, get a PhD unless the program is going to fully fund you.  LIke Laura, I think a humanities PhD is a bad idea--not because I hate learning, or pointy-headed academics, but because if you enroll in a PhD program, one of the following four things is almost certain to happen: 1) you will drop out before you complete your dissertation.  2) You will fail to land a tenure track job and eventually give up having spent 6-10 years of your life making yourself less employable than a newly minted college grad. 3) You will land a tenure track job and not get tenure.  4) You will get tenure somewhere where you don't want to live, or somewhere far distant from anywhere that a current or future spouse could possibly find rewarding work.  

The odds of actually ending up with a cool job in a good location are very, very, very small.  No, this does not just happen to folks unlike yourself, who really arent' that smart; it happens to good people all the time.  The professors who are suggesting otherwise are people have have won the lottery.  Do not listen to them about the advisability of buying some tickets in the academic equivalent of the Powerball.  

But I digress.  If you do decide to get a PhD program anyway, do not under any circumstances enroll in a program that won't fully fund you.  That program is telling you that they do not think you will get a job in the field after you graduate.  Moreover, they are not going to invest any serious resources in you, in the form of mentorship or professional opportunities, because those things are in limited supply, and they are not going to waste them on someone who isn't going to get a job.    Also, you'll graduate with a terrible debt load, but that's almost secondary to the extremely dim job prospects you will have when you complete your degree.  

What's your advice for prospective students?