Original corner first method

Briefly, I position all corners first.(step1-3) Then, I position edges at the middle layer,(step4) center cubes,(step5) edges at the top,(step6) and the bottom edges. As possible as I can, I make a pair of middle edges and position them both.

Step1. three corners at the top layer. 

I use basic techniques in this step.

Step2. the last corner at the top layer and the corners at the bottom layer. 

When you position all corners at the top layer, you should position them one by one except lucky cases. So, you must meet 3 croners are in good position but the last one is in the bottom layer. In this situation, you can suppose one of the bottom corner cube is in good position. Then, You can position the last corner cube at the top layer and orient all corners in the bottom layer simultaneously. I always suppose the front left bottom corner cube is placed in good orientation. If you are not assure to orient the corner cubes, you had better orient center cube, but I never do that. Off cause, you can use mirror images, but I do not remember them, because I can change the situation only F'. Actually, I only used the first series at the second Japanese championship. The second series were developed recently.

3 corner cubes can be supposed to be in good orientaion at the bottom layer.

2 corner cubes can be supposed to be in good orientation at the bottom layer.

B

C

Only 1 corner cube can be supposed to be in good orientation at the bottom layer.

D

E

F

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