i don't think you necessarily have to follow any rules. it is whatever works best for you. i usually apply the eyeshadow according to what i think looks nice on me. i like to apply colors that compliment one another and that's how i go about layering. layering just really helps the color appear more vibrant, but it is not a necessary step, b/c paints or urban decay primer potion can help you get the colors more vibrant. if you buy shadesticks and pigments for example: sea me shadestick can be matched with blue, steel blue, etc. these are complimentary colors that will help blues become more vibrant. the same for greens, golds, browns and purples. When I am using mulitple colors on the eyes i usually like to go from lightest(inner eye) to darkest(outer eye). Or lightest shade on lid and darker shade on crease, darkest shade on v. That's just me. Just get in there and play around and see what you come up with. I used to read and look at all types of techniques and tutorials, but until I actually just started practicing, that's when I started to understand the concepts and apply the techniques. You will find your style and what works for you!:icon_chee