I leave mine in and burp the jars every day for a week, more if still damp. Last thing you want is mold on your buds that you put so much time and effort into.
When I say burp, I'm talking about leaving the lid off. You can usually tell by how the smallest stems react to bending. If all they do is bend, it's still too damp. If they bend and then snap, they're ready. Chop up a small bud and if it stays lit long enough to get a good toke, you're good to go.
I always stick my finger in the jar. I can tell how the buds feel if they need more air time.