The goal of the Radiesse is to provide volumization and rejuvenation, and while these two issues are closely related, they sometimes evolve in different ways as you are injecting. Because of this, I feel that the initial markings are not as crucial as is re-evaluation of the overall aesthetic as Radiesse is injected. Early on, I did mark patients prior to injection, but at this stage, I find markings get in the way of subtle but crucial rejuvenative changes as I inject.
Having said that, commonly marked areas are the malar mound (cheek fat over side facial bone), nasolabial fold barriers (border between middle part of cheek and lips, also called the "parentheses" of the face), marionette line barriers (prejowl area in lower face), and temporal areas (hollows in front of side hairline). The markings help define specific aesthetic subunits of the face.
Thanks again for your question. Hope this helps.