Draw a large oval shape for the main body
Add a pointed bottom to form the apex
Draw two smaller upper chambers at the top
Sketch the right atrium on the upper left side of the page
Sketch the left atrium on the upper right side of the page
Draw the right ventricle below the right atrium
Draw the left ventricle below the left atrium
Add the septum as a vertical dividing line inside the heart
Draw the aorta as a large curved tube from the top
Add the pulmonary artery branching from the top center
Draw the superior vena cava entering the right atrium from above
Draw the inferior vena cava entering the right atrium from below
Add the pulmonary veins entering the left atrium
Outline the coronary arteries on the surface if needed
Label each chamber and major vessel
Darken the final lines and erase extra sketch marks