If you've got an idea of your own, then try it out. If not, here are three ideas to get you started. Poems with rhyming couplets have pairs of lines which rhyme. If I Was a Rich Man I suppose I would like to be wealthy Tho' with a choice I'd prefer to be healthy. Haiku poems only have three lines but they follow a strict pattern.
Haiku often describe 'a moment in time'.
In brightening our dull world. We should do the same. Limericks have 5 lines. The first, second and fifth lines rhyme, and so do the third and fourth lines. Limericks tell funny stories.