Measure the width of your bed. Standard queen-size mattresses are 60 inches wide, but the actual width of your bed will depend upon the type of frame or platform you are using.
Choose doors of the same widths and heights that, when the widths are added together, exceed the width of your bed. Front doors are typically 36 inches wide. Two would suffice for most beds but don't be afraid to line up three or more narrow doors.
Remove all hardware from the doors and wipe them down with a damp cloth. If you got them from a salvage yard, scrape any peeling or blistering paint off the doors. Put on a dust mask and protective eyewear. Sand the doors with a medium-grit sandpaper. Wipe them clean with a damp cloth.
Fill all holes, mortises, dents and/or gouges in the doors with a wood filler using a putty knife. Allow the wood filler to dry according to label directions.
Sand the doors smooth with a fine-grain sandpaper. Wipe with a damp cloth.
Prime the doors and paint them the desired color using latex products. If the doors have panels, consider painting them a complementary color or stenciling a design in the panels. Allow the paint to dry for at least 24 hours.
Center the doors, side by side with no space in between, behind your bed. Use a level to ensure they are straight and adjust if necessary. Mount the doors using mounting brackets designed for mirrors or heavy frames, following the manufacturer's directions using the appropriate tools.
Put your bed in place, moving the head as close to the doors as possible.