The beginner method to solve a 4x4 is called reduction. The first step is to solve the six centers. This step is generally done intuitively. The concept explained in this 4x4 tutorial is to make a "bar" (2 centers pieces together) and then put the bars together to form a center. Because the centers of a 4x4 is not fixed, the catch tough is to put it the correct position relative to the centers that we have already completed.