Explain the procedure of substitution in the game of basketball.

Procedure of substitution in basketball: 1. Only a substitute (or the team's coach) can request a substitution, by going to the scorer's table and clearly signalling the request. 2. The substitute must wait outside the court until the scorer signals and the referee calls him in. 3. A substitute may enter only when the ball is dead and the game clock is stopped. 4. A player who has been substituted may re-enter only after the ball has been dead and the clock has been running.