Hmm
There are blogs like @pronoun-provider and @pronouns-archive that have a whole list of neopronouns that you can look at in addition with my nounself recommendations if you’d like!
You could use a set like clo/clow/clows/clownself or smi/smiles/smileself. And depending on specifics of what clown you are, you could incorporate color based nounself pronouns, items you used specifically (like balloons, pies, ect), and any other detail. But I hope that helped!