Whether through loss or breakage, you may find yourself in need of replacement slats for your twin bed frame. These can be made with supplies readily available at your local hardware hardware store for a couple of dollars a slat.
Measure the width of your twin bed frame where the slats will be placed. Allow for the slats to slide easily into place. Note how many slats you will need to make--a bed with no slots will usually require about 12.
Obtain 1 x 2 piece of lumber from your local hardware store. Any hardwood will do, but be sure there are no large knots or splinters in the pieces. Get as many pieces pre-cut to your earlier measurements by the hardware store as you need for slats.
You may choose to sand the slats if they have rough edges so that they do not snag and tear your mattress or box spring. After sanding, it is recommended that you seal the wood to keep out moisture and bugs so it lasts longer and is easier to clean. Do this by following the instructions on your sealant.