The infrared decision tree represents one way to approach reading spectra. You may note that it is fairly efficient, and that it focusses on the strong and reliable absorbances first (carbonyl and X-H stretching) and proceeds to put less reliable data in context.
To use the decision tree, start at the top, and ask the questions suggested by the labels on the vertical lines. In each case, if the answer is "yes", follow the tree to the right, and if the answer is "no", follow it to the left. Each place on the tree indicates the history of decisions you have made (for example, decisions for the ether are "no" to carbonyl, "no" to OH stretch and "yes" to C-O stretch).
This is a graphical form of the more detailed approach given at "Interpretation of Infrared Spectroscopy."
