This is a tutorial that shows how I made my beach background for my Beach Baby Doll. It's got a lot of ideas that can be used for other beach and waterscape scenes, such as the kind of hues for the water and the sky and when to dither and when to AA. It is NOT an explanation of colour picking, dithering or AA themselves, but involves those things. Watch out for tutorials in the future for those things specifically, I simply can't cover them all in one tutorial
Does require the user to have small, basic knowledge of terminology such as "dithering", "AA" and "hue". Therefore I would recommend this for intermediate difficulty and above.