Develop a money plan
Map out with your child just what his or her expenses will be and what cash you can make available to meet those expenses. If your child has already had a year or two at college, you'll have a better sense of where they've overspent in the past. So now's a good time to explain the value of work if their desired expenses exceed their means.
Discuss with them what kind of job (and paycheck) they can get to make up the difference, and ask them to consider how that job will affect their studies and other obligations. If they discover they have to work long hours just to support their spending, that's a sign they might be better off cutting back their costs.
Create a written budget
Have your child make a list of all their monthly bills, the due dates, the account numbers and the addresses to which payments ought to be sent.
They've got to get on a regular cycle of paying bills. The fact that they write it down makes an impression.
Pack the credit card
Your college student is of age and can get a credit card -- or six -- without your permission.
But you can still keep an eye on spending -- and perhaps reduce the urge to sign up for a credit card on campus -- if together you arrange to get a card on which you're a cosigner but which is in the child's name. That way you are both responsible for the charges and you have access to their monthly statements.
Or you can make your child an authorized user on one of your credit cards. Only you will be responsible for the charges, but your child can use the card to make purchases.
One option is to get a credit card with a low fixed annual percentage rate that doesn't have an annual fee and allows parents to set a credit limit as little as $500. This will force your student to pay attention to their spending, and ensure that they don't surprise you with an enormous credit bill.
And you should spell out about what types of charges you'll pay for and which you won't. Make clear that charges you don't approve of will come out of your child's allowance for living expenses or they'll have to make the money on their own.
If your child does opt to get a card in their name, encourage him or her to shop for the best deal (low APR, no annual fee) and not to be swayed by the "free gifts".