What can we learn from the service rituals of the top players if they all have different routines?
But although their rituals are different, there are three component parts that all the Great Servers use in their service rituals.
They look down, and relax, often but not always bouncing the ball. Then they look up, seeing the opponent and planning the service (this is often called visualisation, but if you think of it as planning it is a simpler concept).
Then they collect the ball into their sight and begin the service.