This keeps the line from bouncing and tangling on the rod. Certain steamers absorb water slowly and aren't ready to fish when first tied on. Wet them down in a resealable sandwich bag and they'll be ready when you need them. To avoid injuring fish when handling, turn them upside down. This eliminates the belly squeeze.
Most fish become disoriented and lie still.
A safety pin attached to the front of your vest will clear it out. It's always handy when you need it. Maintain a special box to store and identify those single samples of hot new flies you acquire. Make notes on a small slip of paper and put it in the compartment with the fly. With the new book, I won't have to.