oh god this is sloppy I literally took less than half an hour to make this.
Anyway, further reading: The-Godlings-Rapture's tutorial
This is the tutorial I always recommend. THIS is the ultimate pixel tutorial that explains everything explained here so much betterKiwinuptuo's color palette tutorial
This is also a great tutorial that explains color palettes
Other tutorials:Jazisnake's color and pixel texture tutorialPurplekecleon's color tutorial
Pokemon (c) Nintendo
Art (c) Amethysttiger