A do-it-yourself inflatable bed can be created with a bed frame that resembles the frame of a waterbed. Materials needed to create such a frame will generally include some 3/4-inch plywood and some 2-by-4s. You can easily construct a rectangular bed frame from these materials to create a box-like bed frame to go around the air mattress. This frame will help hold the mattress in place and keep it from sliding around and moving while you sleep.
Another option for a do-it-yourself inflatable bed is to simply use an inflatable air mattress buttressed up against a headboard that is flat against the wall. When properly covered, this will make the bed appear as a permanent furniture piece in the room and will not generally be distinguishable from a bed with metal frame attached to a headboard. These beds are easier to move than those made to mimic waterbeds.
The simplest way to create a do-it-yourself inflatable bed is to purchase an air mattress in the size of the bed you wish to sleep in. Some air mattresses are as high as a regular bed and can mimic the feel of these beds up to a point. You can also purchase one of the thinner air mattresses that are often used for camping and more closely resemble an air raft that you would use in a swimming pool. In fact, some of these air rafts can also double as an inflatable bed.
Bedding material is key to making your inflatable bed look like a permanent fixture in your home. Aside from your normal pillows and covers, you can also create a makeshift bed skirt to disguise the bottom of your bed. Realtors and builders with model homes will occasionally do this in homes they are showing in order to stage the home for sale. The simplest way to do this is to find a decorative material at a large retail department store or in a hobby store. Use duct tape to tape the top edge of the material high enough on the side of the mattress that your bedspread or comforter can hang over the side and cover up the tape. Allow the material to hang to the point that it just barely grazes the top of your floor or carpet.