A dog bed can be made out of materials you have around the house. Using a cardboard box, cut it to form the shape of the bed. Then, put an old pillow into the box to act as the cushion. Or, you could use and old blanket, sheet, or a few shirts.
Making a dog bed id just like making an over sized pillow. Find the material that you want to use, fold it in half, and sew it up on both sides. Then fill it up with stuffing, and sew up the last side.