Step 2: Centers

In the next step, solve the three large centers to the right of the first block. These are the F, BR, and U centers. Only two need to be solved and the third center will be automatically solved.

The front and back right centers will be solved. Once those two centers are solved, the upper center will be automatically solved. Solving the centers follows a similar process to solving the center in the first step, where half centers are built and combined. The move set is now reduced to U, R, r and slice turns. This will feel familiar to those experienced with the center solving process of big cubes.

In the example, the centers will be solved in a specific order. But the centers can be solved in any order. Solve the best center for the scramble.

Attach triangles and edges to form a half center. In the following images, a triangle from the bottom is attached to the edge on the upper layer.

An edge will then be attached to the two pieces to form a half center. In the images, U' R U' R' is used to move the to pieces on the upper layer out of the way, position the edge, then restore the original two pieces.

With the half center completed, it can be moved to the left side of the upper layer then solved to the back with the use of an r turn.

Form the other half center by first pairing two pieces. In the following images, R U R' is used to connect the triangle and edge on the upper layer.

The final piece is attached to form the half center. In the following images, U' R is used.

Turn the upper layer to position the half center, then attach it to the previously built half center.

To solve the second center, attach a triangle and edge. In the following images, the triangle on the bottom is attached to the edge using R U R'. Be careful during this step to not break the first center that was built. This can be avoided by ensuring that the right side layer is always restored after a turn of the upper layer. For example, R U R' or R U' R'.

Locate another piece to form a half center. In the following images, there is an edge at the front right position. The upper layer can be turned to move the first two pieces and prepare them for placing the edge.

The edge is then solved by moving the two pieces out of the way then restoring afterwards. In the example, the sequence r U' R' U' M is used to attach the edge and solve the half center.

Solve the final half center using the same strategies. Pair up a triangle and an edge then simultaneously attach the final triangle and solve the half center. In the example, R U R' is the ending sequence of turns. The final triangle won't always be on the front layer. Sometimes it will be on the upper layer. In those cases, turn the upper layer to move the two attached pieces to the right, then use R U R' or R U' R' to place the final triangle on the front layer.

If there is a situation where the last triangle can't be connected to the other two pieces using a single move, the lone triangle can be moved to a better position. In the images below, R U' R' is used to move the triangle to the bottom position. Then the triangle can be solved normally using U' R U R'.

Sometimes the final half center will be pre-built on the last layer. The pieces can either be intuitively separated then solved, or the following sequence of moves can be used. Thanks to anja.k4 for providing this algorithm.