We are over-thinking this. The Sacred Valley loop is very obvious and it's just about impossible to get lost. Just follow the road signs, you will figure it out. Cuzco, Pisac, Urubamba, Ollantaytambo, double back to the Chincheros cut off and crank up out of the Valley floor up to Chincheros and maybe take the side road to Moray/Maras and do some exploring, then back to the main road to Chincheros and Cuzco. I'm making this sound more complicated than it really is so sorry about that.