Understand how the money is handled before you get it. Most grants and loans are automatically applied to your tuition first, so you don't have to worry about that. After that, most schools will write you a check for whatever is left over.
Be smart. Just because you can spend your money on whatever doesn't mean you should. As a general rule of thumb, you should stick to spending money on school expenses such as books, room and board, and transportation.
Visit a financial aid counselor. The quickest way to find out is to ask your school's financial aid office. They have the final say on all matters of financial aid.
Explain extra expenses (dental, car repairs, computer) to your financial aid office in full. Depending on the institution, your circumstance may demonstrate sufficient need to expand your loan.
Bring a copy of your rent contract and utility bills to be confirmed by the financial aid office of your school. If you are living off campus, you can get your school to include your bills in the cost of attendance.
Consider meeting with private lenders. Private lenders will usually have loan terms delineated on paper as well as explained to you in person. Alternative, non-government loans will vary widely in their terms.