A squeaky bed frame is annoying. If you live in shared housing, the squeaking probably annoys your roommates as well. As you move around on the mattress and box spring, stress occurs where the nuts and bolts hold the metal frame together, causing the squeaking. Tightening the nuts and bolts may temporarily fix the problem, but there is a better long-term solution: Stop the metal parts from rubbing against each other.
Lift the mattress and box spring off the bed frame. Ask someone to help you if the bed is queen or king size.
Undo all of the bolts, washers and nuts holding the bed frame together with a crescent wrench.
Wrap each bolt with sealant tape until the threads are completely covered. Slide a plastic washer over the bolt threads up to the head of the bolt.
Stick the bolt back through the hole in the frame. Slide a plastic washer onto the threaded side of the bolt until it touches the frame. Slide the metal washer onto the threaded end of the bolt, and then follow it with another plastic washer. Screw the nut back onto the bolt threads with your fingers.
Place the crescent wrench back on the nut and bolt, then tighten. Repeat with all nuts and bolts. The bed will not squeak, as you have removed metal-on-metal contact.