I'm currently putting together a new character model, so I thought I'd document the process I use. It makes creating a new character from scratch pretty quick. The idea is to quickly block out the character's proportions first using simple cubes, spheres, and cylinders. There's no need to worry about the topology/edge-flow, just quickly flesh out the smaller shapes that make the character.
These basic shapes can be quickly manipulated into place using lattices and proportional modeling.
Lattices make it easy to warp geometry using a simple cage.
Proportional Modeling adds a fall-off to the basic transforms.
The workflow becomes as simple as mashing many meshes together, and quickly warping them using the above tools to get the bigger shapes you want.
Breaking an otherwise complicated object into much simpler shapes makes creating them easier and faster.
Before you know it,you'll have a character fully flushed out,with most of the harder work eliminated.
All that's left is to turn it into a more proper model, which is very easy to do.Now you're free to focus on the topology without worrying about the shape of the model itself.