Side Panel On Center Console, Rear:

Slide panel (1) on left/right in direction of arrow and remove.

Fig 1: View Of Side Panel On Center Console (Rear)

Courtesy of BMW OF NORTH AMERICA, INC.

Installation: 

Retainers (1) must be correctly seated in panel guides (2).

Fig 2: Locating Panel Guide Retainers

Courtesy of BMW OF NORTH AMERICA, INC.