Side panel on centre console, front:

Release screw (1) on left/right.

Fig 1: Releasing Screw On Left/Right

Courtesy of BMW OF NORTH AMERICA, INC.

Slide panel (2) on left/right in direction of arrow and remove.

Installation: 

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

Fig 2: Identifying Retainers

Courtesy of BMW OF NORTH AMERICA, INC.