The Heise method proceeds as follows.
1. Build 4 squares
Build 4 successive squareshaped blocks, attaching each one into a bestfit position. An interesting feature of this step is that the squares need not match in colour, which gives you the freedom to take advantage of squares that may already be partially built, no matter what colour they are.
Learn more about building squares.
2. Match the squares and orient the edges

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In this step, we match up the squares (if they are not already matched), and orient the remaining edges. At first, you will learn how to do this as two separate steps, and then simultaneously as one step.
Learn more about matching the squares and orienting the edges.

3. Solve the remaining edges and any two corners

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In this step, we solve all of the remaining edges and any two corners. At first, you will learn how to do this as two separate steps, and then simultaneously as one step.
Learn more about solving five edges and two corners.

4. Solve the last three corners