Beds and large pieces of furniture with wood or metal legs often slip on hardwood floors, leaving scratches and removing the floor finish. For furniture that remains in position for a long period of time, such as a bed, there are many ways to keep the piece in place. There are other options for more mobile furniture that is periodically rearranged.
Apply rubber furniture cups under each leg of the bed to lock the bed to the floor. These universal grips are easy to use and are inexpensive. They are visible and will not work with all furniture leg shapes.
Invert the bed and affix both sides of heavy-duty Velcro to the bottom of the foot. Trim as necessary to fit the shape of the bed leg. This is not standard Velcro and the two parts have to fit together. Leaving the paper protecting the glue on the Velcro, put the bed frame together and position it exactly where it should go. Raise the bed a few inches and remove the paper (it helps to have two people doing two legs at once). Set the legs down and wiggle them slightly to seat the Velcro. Velcro glue can be removed later with a glue remover.
Apply gripper pads to the underside of the bed legs. These rubber grips are easy to work with because they have a self-stick backing and come in many shapes. The rubber won't completely stop a bed from moving but it will make it much more difficult to move. This style cannot be seen when in place.
Install bumper feet in much the same way as gripper pads. These tend to be taller than gripper pads and they are often used to completely stop the movement of glass table tops. There may be a slight give when pushing against the bed firmly.
Invert the bed legs and cut the shelf liner to the correct shape. Lay the liner between the bed and the floor. This method is inexpensive and doesn't use any glues so there will be no residue to clean at a later date. The bed should hold position against movement and the liner can be cut so that it can't be seen.
Carpet underlayment can also be used like the liner. Rubber tub matting will probably work like the shelf liner and it is also inexpensive. Most of the bumper type will flatten over time and some of the adhesives aren't as strong. Some older hardware stores also carry screw-in type bumpers that are rubber disks with a hole in the middle.
Most non-skid material will give under sufficient force. Different floor surfaces and finishes will make different products more effective.