A great serve starts before you even reach the baseline. "When you walk to the line, you always walk hard," says Venus. "You don't walk up to the line looking doubtful, you walk up as if you know how to serve. You walk up with an attitude because you know you can do it. Even if you don't know, you step back and you try again. You walk the right way to the line."
In tennis, a game defined by both action and pauses, every service point presents a chance to take control and set the tone. Williams actually visualizes the trajectory of the serve to secure her focus. "You're visualizing the ball going where you want it to go," she says. "You're believing that it will be there."