In the case of the beginner at fly-casting, the first practice casting may best be done casting downstream as the current will help to straighten out the line and leader. Two distinct motions constitute the complete overhead cast; first the back cast which throws the line behind the caster, then the forward cast which returns it in the desired direction. Fifteen or twenty feet is enough line to use for the first practice casting. The right hand should grip the rod firmly with the thumb extended along the upper surface of the handgrasp--this is the only proper grip of the rod and is a distinct factor for accuracy in placing the fly and also tends to make the caster use his wrist.
Good casting results only from utilizing the elasticity of the rod; the casting power of the rod is brought into play in one way only--by using the wrist in casting. Keep the elbow low.
In the back cast swing the rod smartly up to a position but slightly beyond the vertical and inclined a little toward the right so that the line when passing to the rear, or returning, will not tend to strike the rod. In the back cast throw the line up in order that there may be no possibility of its falling upon the water behind you--a high back cast is very essential. Lift the line from the water quickly and neatly. Care must be taken not to carry the rod too far back--only a little beyond the perpendicular--as this will inevitably result in loss of control over the line.
Instantaneous photography has conclusively proved the fallacy of the orthodox advice of the older school of angling writers, to "wait for the line to straighten out behind you" before starting the forward cast. This fact was noted sometime ago in a short paper in one of the outdoor periodicals and the writer at once proceeded to verify it--since which time I have often seen in print the old, familiar warning to the novice stated above. However, it is now generally recognized by well-informed anglers that when casting any fair length of line there is a considerable loop of line and leader which straightens out only after the forward cast has been started; that, in fact, the right time to begin the forward motion of the rod is when the line first begins to pull noticeably on the tip of the rod--a psychological moment soon readily recognized after a little practice. To avoid weakening the leader by whipping, or in rare instances snapping off the fly, the forward cast should not be started too forcefully.