Quantum materials represent a broad class of systems whose experimental response relies on uniquely quantum aspects such as entanglement, Berry phases, and electronic correlations. Modeling of such materials presents challenges related to a variety of complex behaviours that manifest at different temperature and frequency scales. In this field, first-principles approaches often provide a vital bridge between experiments and theoretical models. In this talk, I will introduce our numerical strategies for systematically building low-energy models starting from a crystal structure and ending with models for local charge, spin, and orbital degrees of freedom of arbitrary complexity. Time permitting, I will also discuss preliminary work extending these methods to treat (i) spin-phonon coupling, and (ii) non-linear responses in quantum materials.