I grow my own and it's a bit early for me to pick them yet, last year it was mid September. You want them to have a strong hoppy smell when rubbed but catch them before they start to go brown. I dry them for a few days on a clean tea towel and when completely dry pack them into brown paper bags where they keep for months. If you use wild ones for brewing I'd suggest making a small batch to test them first, I've had variable results using wild hops. Remember where you found them as you can eat the hops shoots in the spring.