In your drawing program of choice, use the line tool and set the line thickness to 1.
Then you can draw over the template lines.
Keep in mind that every shape gets distorted in any projection, including Isometric.
You can use shapes to construct anything, like a person, a cup of coffee, or an omelette, for example.
Also keep in mind that complex shapes can be simplified into basic shapes.
When I shade shapes, I usually should change the hue to be closer to blue, and decrease the saturation.