Center 4: next to the third
Step 1 / 3
r: Right inner layer: turn 90°, front face goes up (Written as TR in the textbook)
Orange is at the back, the first two centers on the left and right. The top is missing its left column; the front has a blue bar of three in its right column.
Solve blue on top, next to orange. That way the last two centers are neighbors, as the next lessons need.
Step 1 of 3: r. Right inner layer: turn 90°, front face goes up