Hooking a fish in rough water requires little action on the part of the angler — just a slight lifting of the rod. In other places the fly fisher must " strike " his fish. This is done by a slight twist of the wrist. . In fact the failure to hook rising fish is the most discouraging part of trout fishing to the novice. It calls for alertness and a little knack — a canny wrist the Scotch say — that will come with experience. A young trout fisher never strikes too quickly and he should train himself to keep a taut line at all times and to strike immediately he sees the flash of a fish. If the fish rises and misses the fly, rest the water for a full minute before casting again. If the fish is pricked leave that spot for a few minutes; then come quietly back and try again. My experience is that a pricked trout will often strike again if left alone for a while.