At this stage we define location like points (?) and a respiratory triangle (?) (I do not know how it is called) and the direction of turn of the head.

We start tracing, we do everything by thin lines.

We start drawing a helmet.

Draw part of a helmet, cervical area and shoulders.

We draw helmet details.

We trace a helmet. Press the picture for increase.

Draw filtering and respiratory part of a mask of Darth Vader.

We draw patches of light on glasses.

In nasal part.

We do a shadow in a helmet.

Still we apply a shadow on a neck and area of a raincoat.

Look still Yoda from Star wars, and also the head of a dragon, the spiderman.