Why do clowns make silly faces? from a question on Quora
To make people smile and laugh.
That’s it. That’s all there is to it.
A clown’s job is to spread laughter. Silly faces help to do that. I did that last Saturday at a birthday party, and made a silly face for a 1-year-old — and he laughed and giggled. I did the same with his parents, and they laughed. And the grandparents. And the other guests.
In short, clowning is (or can be) an invitation to laugh, and have fun — and a silly face is just one way to send out that invitation.
Have fun, and bump a nose!