The middle layer contains four edges without the top or bottom color. After finishing the first layer, hold the completed color on the bottom and find an upper-layer edge that does not contain yellow.
Follow the lesson
Choose a suitable top edge
Ignore top edges containing yellow. Take one with two side colors and line up its front sticker with the front center.
Decide left or right
Look at the other sticker on the upper edge. It tells you whether its matching slot is to the left or right.
Insert to the right
With its front color matched, use U R U’ R’ U’ F’ U F when the target slot is to the right.
Insert to the left
For a left target use U’ L’ U L U F U’ F’. Check the bottom layer afterward.
If no useful edge remains on top, insert any top edge into a wrong middle slot to eject a misplaced middle edge. Then solve the ejected edge normally.
Practise it on a real cube
Keep your physical cube in the same orientation as the instructions. Perform each face turn slowly, stop and check the stickers, then compare with the 3D trainer. Voice lessons can guide screen-based practice; physical cube moves are confirmed by the learner rather than checked by a camera.
How to know you are ready to move on
Repeat the exercise from a fresh starting position and explain what each turn is meant to accomplish. If the result differs from the target, go back to the earliest step you can verify instead of immediately starting over. Use cube notation whenever a move symbol feels unclear.