So then, I've got my blobs of putty the next step is to make sure they are all roughly the same dimensions. This stage needn't be too precise as the entire 'blob' will be covered with face it's really just a starting point.
First off I trim the blobs so they are thinner and shorter that I want the finished product. I tend not to reduce the depth as they are intended for casting and there will inevitably be some shrinkage. Although shrinkage occurs to the piece as a whole it will be most noticeable front to back so I try to make things a bit fatter than they will end up.
Next I take a file and cut a gash across the blob roughly two thirds of the way up. Human eyes are roughly half way down the skull but seeing as I'm making faces specifically rather than heads it's not really a worry. When the head is added to the model I like to have plenty of depth available for adding texture to hair so I leave off the top of the head to give me the room.
Right, so the blobs are ready for the first bit of detail. Stay tuned.