Glue two 10 1/2-inch-by-9-inch top and bottom panels to two 12-inch-by-9-inch side panels. Secure the panels with finishing nails.
Glue the 12-inch-by-12-inch back panel to what you assembled in Step 1. Again, secure the wood with finishing nails.
Screw the entire cubbyhole to the wall directly through the back. Use two screws, one 4 inches from the bottom and one 4 inches from the top, centered on a stud.
Place whatever items you need to store in the cubbyholes.
Put wooden dividers in any drawers to keep things neat and organized. Bathroom drawers are just as susceptible to becoming messy as a kitchen junk drawer. These dividers come in various shapes and sizes, meaning the perfect fit can be found for any drawer. When picking out a divider, think about what you want to store in the drawer (toothpaste, makeup, first aid supplies), so you get the appropriate size.
Assign everyone who uses the bathroom their own drawer or cabinet. This keeps everyone's products and toiletries separate, allowing everyone to know exactly where their things are when they need them. It also prevents one person from messing up everyone else's stuff.
Install two-sided magnets in the back of your medicine cabinet, provided it is made of metal. Some magnets have hooks on them, so you can hang scissors and other bathroom products on them. Other metal toiletries, such as tweezers, will stick directly to the magnets and free space on the medicine cabinet shelves themselves.
Attach three metal towel bars to the back of your bathroom door. You can hang towels on these bars and save space in the bathroom. Follow the package instructions and space the bars evenly down the length of the door.