Help with Noob Head Modeling

ok. Im a…amateur at using Blender. I wanna make a head. Which will later be added to a body. So how do i do that?

I know how to use basic Sculpt functions and how to extrude and scale a box and crap and use subsurf and stuff.
So how should i make a detailed head…or…a whole human body?
Some help or tips please?