Bed frames made from strips of wood are attractive, but sometimes they squeak as you shift on the mattress. Applying the right lubricant and replacing cracked or weak pieces of wood will prevent the slats from squeaking underneath the pressure of your mattress.
Remove all bedding and the mattress from your wood-slat bed frame.
Remove the wood slats from the bed frame. Lift them out by hand, as they normally aren't attached to the frame. If they are attached, unscrew any screws or pry the nails out with a hammer claw.
Wipe a block of paraffin wax along the frame edges where the wood slats sit. This will lubricate the surface and prevent most squeaking.
Inspect the wood slats for signs of cracking or excessive bending -- both conditions indicate weakness, and are possible causes of squeaking. Replace any slats that show evidence of cracking or bending.
Replace the slats on the bed frame. Reinstall the mattress and make the bed.