As far as simple styling tricks go, layering is nothing more than wearing clothes on top of other clothes. Unless you're totally naked under your parka, you can't not layer in the colder months, which makes "winter layering" a no-brainer sort of fashion move that everyone basically participates in. But, just like you can't say you're a bona fide chef because you can scramble eggs, you can't claim to be a skilled layerer if you're just wearing a cardigan over a tee. To really take advantage of all the fun you could have with shapes, textures, and colors, you've got to flex your fashion muscles a little harder.
This season, you should rethink anything you've assumed about what inner layers look like and what outer layers should be. Mix things up, change the order, and go against convention (that sweater doesn't have to go on your arms, for example). Even so, it's not that complicated. Your seven-step primer, right this way.