Step 3: Solving the first layer of the Pyraminx
You choose the starting face that you will turn to the bottom. You can choose the face that has the most correctly solved parts, since it makes no difference what colors will be on your starting face.
According to the colour of the starting face in this step, we will only solve the side two-colored parts that contain that color.
In our example, the base color is yellow so we can now find the following two-colored parts of the Pyraminx:
We begin by rotating the middle layer, bringing the part that we’re solving towards the face whose lower diamonds are of the same color as that part.
It is important to pay attention to whether it will be above the left or the right diamond, for that decides which algorithm to choose in order to solve the Pyraminx.
In the case of our example, we first solve the yellow-red part – we turn the Pyraminx so as to face the red color and use the rotation of the middle layer to bring the red triangle to face us, while the yellow one goes behind. We emphasize the matching of the red triangle with the right red diamond. Next follows the algorithm L'UL for lowering the yellow color into the first (basic) layer.
After we do this algorithm we turn the whole Pyraminx so as to face the green color. We emphasize the matching of the green edge triangle with the left green diamond which leads us to the second algorithm RU'R'.
In our example, the starting position of the yellow-blue part was in the first layer and at the correct position. It may happen, however, that some of the border two-colored parts are in the first layer, but at the wrong position – when that happens, we should use these same algorithms to bring them to the middle layer, to correctly position them and to bring them down to the first layer again.
Upon completion of the first layer we are only left with solving three other parts of the Pyraminx.