EPISODE 1 is a simple one, which applies to the digital editing stage: straighten your (bloody) horizon! In other words, make it HORIZONTAL! I'm amazed by how often I see photos by very good photographers where a duck is swimming uphill, or an African plain is slanting away at a 15-degree angle. Failing to level up a photo is a good way to make an otherwise excellent photo look terrible. And actually, this is most often messed up in photos where the "horizon" isn't actually visible, as in the example of the uphill duck. Even without an obvious horizon, your eye wants a photo to be level, and if it's not it's going to seriously impact your appreciation of it. I post this photo of a Southern Oryx is an example. The first thing I did when I Photoshopped this image was to rotate my crop so that the horizon was... horizontal!