For this achievement, it can be done in coordination with Ending 22.
First, hit the red button once.
You may notice a small right facing arrow next to the red button. Click near where the arrow points and another arrow should appear.
Follow where that next arrow points and click in the direction it points along the whole area until you hit another arrow.
Repeat this 6 more times and you should eventually hit a button that opens up a 3x5 panel of green buttons.
To solve the pattern in six moves, follow this diagram:
[3][4][x][x][1]
[5][6][x][x][x]
[x][x][x][2][x]
Using this diagram, hit the numbered buttons in numerical order.
After doing so, you will not only have completed Ending 22, but now have the achievement.
Credit goes to Drea Warrior Princess who made this guide which I used to get the achievement myself (and has images if my explanation wasn't good enough):
https://steamcommunity.com/sharedfiles/filedetails/?id=46348...