When you are drawing one of the first things you are taught is to see the shapes in your subject.
The same goes for sculpting.
I will give you an example of a simplified version.
If you had wanted to sculpt this owl you would break it down to its basic shapes. So to do the body you would start with a ball of clay.
The beak would be a little triangle of clay and the toes would be little snakes. Which you then blend into the more complex shapes.
So when you are getting ready to sculpt, create a mental overlay over your reference and see the shapes before you begin.