Keep feet shoulder width apart, weight slightly over the right foot. You should bounce the ball outside of the right foot. The hand should absorb some of the energy of the ball striking it by moving slightly on impact, and returning to the starting position whilst the ball is still in contact with the ball.
NOTE: The hand should remain on the top of the ball only to prevent carrying.
Rebounding is the least glamorous thing in basketball and one of the most decisive. It is also almost entirely a habit, which means it is entirely coachable.
Good spacing is only the start. The best modern offences teach players to attack the defence's rotations and play in a permanent 4-on-3 - here is how to coach that read.
The ball screen produces almost half of all professional offensive possessions, yet most teams still teach it as a memorised play. The modern approach trains the read - giving players a framework to decide based on what the defence does, not what the coach called.