While sort of plodding and very rote, I know many teachers start with the Suzuki method, at least for a novice student. The method takes the form of a series of volumes, with the level of difficulty increasing with each volume. Not only does this allow you to self-select a starting point based on your existing skill level (if any), it also gives you a large library of material calibrated to be the right degree of challenging for your current level of skill. The first volume is very easy, so even a total beginner could likely work through the excises, and it's great for autodidacts, since the booklets explain the material and theory very thoroughly.