Step 1b: The height of a young boy will be roughly six heads tall. That means that however tall you drew the head, his proportionate body should be about six of those same-sized heads stacked up on top of each other. A younger boy’s body would be fewer heads in height. An average full grown man’s body would be seven or eight heads high, depending on how tall you want to draw him.
Drawing six head can be tedious, so you can just roughly estimate what six head is or make horizontal marks all the way down to help you determine the height. You can also use a ruler for a more accurate measurement.