Skip option is in the [ESC] menu after starting each scene.

When there is only one unchecked scene, choose the unchecked scene.
Never choose checked scenes.

After the first 3 scenes, you will have multiple scenes to choose from. Choose them in the following order:

1. Bottom left (First achievement will trigger at the end of this scene.)
2. Top right
3. Bottom right

After that, you will only have one scene to choose from again.
Follow the unchecked scenes to the end.

If you chose incorrectly, you may miss a scene and end up at 3/4 achievements.
- If so, you will need to Reset your save.

Side Story is not needed for achievements.

----------------------------------------------------------------------------------

Thanks to Hikikomori and other early players in 100Pals!