Parity: cross 1
Step 1 / 13
l: Left inner layer: turn 90°, front face goes down (Written as TL in the textbook)
Back edge: the left wing is flipped, the right wing belongs to the front edge. Front edge: the left wing belongs to the back edge, the right wing is flipped.
The last two edges at the front and back of the top.
Step 1 of 13: l. Left inner layer: turn 90°, front face goes down