The first thing you need to do before starting a project is to have an idea. It doesn't need to be precise from the start and you don't need to have the whole process planned out from the beginning, but you need at least the general direction. In this case I want to do an old musician (old, but still rocking) with a cool attitude. The next step is to gather references to refine the idea and start planning what it is I want to make.
I start by looking at pictures of the Rolling Stones, Ozzy Osbourne, ACDC and then Bruce Springsteen. I'm going to use all of these musical icons as references for this project. The goal is not to recreate any of these characters, but to try to capture their cool and relaxed feel. I also want to create a funny mouth shape and show my old man blowing out smoke, so I gather references to help create that look as well.
The next step is to create the base head to work on. Sometimes I create a very rough head model in ZBrush, which I then sculpt from a cube. When I do this I focus on creating the main features like the eyes, nose and ears etc. I don't add any detail at this point, but take it into 3ds Max and then rebuild the topology using the Polydraw option. Sometimes I just like to start from one of my existing models to save some time. For this model though, I want to build a new, clean base head model with some nice edge loops and make it my new base head model for all my future projects.
Before you start working in 3ds Max it's good to adjust your Units setting (Fig.01). Go to Customize > Units Setup and select Metric for the Display Unit Scale and International for the Lighting Units.
When I model a head in 3ds Max I just focus on the topology of every part (eyes, nose, etc.,). I don't really concern myself with the overall look of the head, because once the model is done and I'm happy with the edge flow, I know that I will be able to bring that model into ZBrush and deform it the way I want more quickly than I could do it in 3ds Max. It's just something I like to do.
I like to model the head by starting on the inside of the different parts. For example, when modeling the nose I start modeling the inside of the nostril and then expand the geometry out (Fig.02). To do this I change my Reference Coordinate System to Screen so I can now move stuff around based on what I see on the screen. Then I select one or multiple edges and extrude them by holding Shift and dragging them where I want to have them. I apply a Symmetry modifier with the Show End Result feature on so I can see the other side of the nose.