Pair and store (right)
Step 1 / 5
Dw: 2 Bottom layers: turn 90°, front face goes right
Two matching pieces sit on the front right edge (upper) and front left edge (lower).
Dw joins them, R lifts the pair, U stores it, R' Dw' puts everything else back.
Step 1 of 5: Dw. 2 Bottom layers: turn 90°, front face goes right