Drawing is a matter of finding the lines and drawing the space around the subject. Hearts have always been popular fare for artists in all mediums. Drawing a heart is not difficult. Adding dimension to a heart is a matter of a few well-placed shadows. As simple a shape as a heart is, adding your own personal touch to the heart can result in very different effects. Adding creative shading can give a simple heart a 3D effect.
Draw a simple heart. Start at the point of the heart and draw without lifting your pencil from the paper. The object is to get the heart with one unbroken line. You can make the heart thinner at the bottom and flare out into the upper left and right side, or you can go for a more traditional approach and make your heart uniform all the way around.
Draw a second line starting at the top of the heart, right down in the dip, and draw one half of the heart along the initial line. Narrow the distance between the first line you drew and the second as you get near the bottom point of the heart.
Go back and darken the first heart that you drew, then lightly shade it in, using side strokes. You can use a lead or graphite pencil for this, or you can do it with a red colored pencil. You might even apply a light shading of lead and use the red pencil over it for a unique color effect.
Shade the space between the colored area and the second line you drew. Make this slightly darker than the main part of the heart. This is the shadow that gives the 3D effect.
Smudge a spot on the heart, right at the top where the two halves come together. Use an eraser or the tip of a finger. Smudging some of the pencil coloring away creates the effect of reflected light off the heart, enhancing the 3D effect.