Okay this is just how I do it, it's a quikie and I'll do something more indepth later.
Step One
Here we begin, to start off drawing a foot, in this case a female foot which is the size of the human head, you'll want to correlate all measurements from head lengths and widths.
To draw the foot you will draw two circles, one slightly larger than the other so that they form a downward slope from the ankle, glance at the diagram below.
Step one |

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Step Two, connect the two circles, creating the outline for your foot, you will want to bisect the smaller circle to form the point of the toes: see following diagram.
Step Four-Toes!!!
Here you will want to add four small circles to the front of the foot, and one large one for the big toe. If you'd like I can add the other foot as well you'll have to get up with me on that one. You may want to add a marker for the ankle, slightly larger for a male, this will also be completed through a circle. See the figure below.

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