We will get all old, this is an alternative to make it to the toilet at night, off-grid or camping.
Decide the high of your toilet seat. For mine, the front leg is 40 cm and the back leg 1.2 m (front and back 4cm x 4cm). I cut 4cm x 1cm strips to cover the sides, and the door attached them with a nail gun and glue.
To make the bucket slide under the seat, I attached 2 u-channels of aluminum. The rim of the bucket will fit in the u-channel. Took a scrap piece of plywood 22mm for the seat: an old door knop and 2 small hinges.
Sand the whole project with 40 grid sandpaper to 100 grid. Protect the wood with a stone sealer with two coats.