A question posed at the nForum asked for a roadmap to learn Lurie's Higher Topos Theory. This MathOverflow question asked for a roadmap to Lurie's Higher Algebra. Still another question asked for a roadmap to learn *derived* algebraic geometry (DAG).

This question asks for a roadmap to *spectral* algebraic geometry (SAG), such as found in Lurie's Spectral Algebraic Geometry, which is more general than DAG, treating, for example, spectra of $\mathbb{E}_\infty$-rings (instead of only DG-rings).

Ideally, such a guide should include helpful sources other than Lurie's book (which are much rarer than references about DAG) and information about which parts should be skipped (at least on a first reading).

Edit: I just found out that this has already been asked at Quora (with one answer).