Watch: Swimming the freestyle
In the freestyle the swimmer maintains a strong and steady flutter kick. The stroke begins with one arm extending forward in line with the shoulder, then coming back toward the center of the body toward the thigh. During recovery the arm is brought back toward the head, keeping the elbow raised above the body. Strokes alternate between arms. The swimmer breathes as needed by turning the head toward the recovering side to take a breath and then exhaling underwater.
Encyclopædia Britannica, Inc.