I enjoy modelling from life but
always take loads of reference photos with my iPhone. These are invaluable when the model is no longer available. Bogana, a fellow ceramics student, only sat for us for two sessions just before Christmas '14 and I intended to work on her over the break. Of course, I didn't - and the clay hardened too much for me to carve as much detail as I wanted e.g. her fingers and toes.
At least, that's my excuse.
I modelled her in terra cotta (red clay) so she matches some of the models I made previously. These reside on my radiator shelf in the hall.