What to do to make this haircut much easier on my hair?

I am getting ready for a haircut, the barber is not here yet, but I was wondering what would be the best way to make this easier on my hair, I have curly hair, it’s pretty long it’s like an afro, and I want to know, should I leave it like this and let him cut it, or should I wash it first? It’s pretty stiff so I think I should wash it but I am not sure.