To make your own clipboard, you will need to find a thin scrap board. If it isn’t the right size, you will have to cut it to fit standard office paper. If you don’t want to bother cutting your board, ask around until you find something approximately the right size. Paint it with spare paint from your shed or leave it natural. When it dries completely, attach a clip like the one in the photo. The clips can be found at office supply stores.
Clipboards like these have a lot of uses. Drawing is just one.
If you are using your clip board to leave messages you may want to attach a pencil to your clipboard with a piece of string or ribbon. This clipboard was made from the top of a wooden box of liquor and the string was found at a second hand store.