Assume you could make it. Assume that it would work.
Your invention doesn’t have to be constrained by gravity or the speed of light. Nor does it have to follow rules of logic. But it can.
What would you invent? How would it work? Who would use it? Why is it a good idea? Describe your invention in every way that you can.
If you finish writing about one invention and still have room on the page, write about another one. Add an illustration or decorate the page any way that you would like.
Write a title at the top, and put the date on the page, too.