In wildlife photography good images are made by combining “previsualization” with a clear understanding of your subject’s behaviour.
Consider this Spotted Deer image as a simple example. It is a well-known behaviour of the spotted deer to go up on two legs to feed on the fresh leaves of the trees; when you see them approach the short trees, you can expect them to “stand up”. You need to be ready with the right kind of setting and composition to make the image.
Normally vertical composition works well for these, depending on the focal length of the lens you are using and the distance between the subject and your camera. In case you have a shorter focal length, go for a horizontal composition and show more of the habitat.
Canon 1DX + Canon EF 800mm f5.6 L IS, ISO 2000, f5.6 @ 1/500, Evaluative Metering -1/3 Stop, Aperture Priority.
Post Processing: Basic levels adjustments, a bit of contrast and sharpness. Used Neatimage to remove minor noise in the image.