Step four: the yellow cross
We need to form the yellow cross on the top. We pay attention only to the yellow colour of two-coloured cubes. At the moment we are not interested in other colours.
Case one: the “L” shape
There are two yellow cubes at the top and with the middle cube they form the letter “L”. The Rubik’s cube is positioned as shown in the photo, i.e. with the angle arms pointing to the left and to the back. The following video shows rotations – algorithms used to form the yellow cross from this starting point.
Case two: the “dash” shape
There are two yellow cubes (at the top) and a middle one between them forming a line, or a row. We put the Rubik’s cube in a position so that this line stays parallel to the front side, and we apply the following rotations – algorithms:
Case three: the “dot” shape
There are no two-coloured yellow cubes at the top; all of them are positioned at the sides. To form the yellow cross from this starting position, we use the two already mentioned algorithms, in any order. Pay attention to the turn of the Rubik’s cube after the first algorithm is completed.
Case four: It may happen that the yellow cross has already been formed after step three; in that case, just skip step four.