I love soccer, sometimes as a goalkeeper, often big foot kick. The correct method is to use the top of the foot to kick, in the end of the run bending the knee, to the hip as the axis of the swing thigh, and then to the knee as the axis of the swing calf, the support foot to stand firm, the process to keep the toes of the foot taut. If it is a free kick, touching the ball instantly inward or outward movement of the ankle can be kicked out of the back of the foot arc or inside the back of the foot arc, more contact you should have some experience. I hope it will help you.