Not sure if this helps...
Consider the wing of a run-of-the mill airplane (civil, not military). The wing is rounded on top, hollow at the bottom. The rounded edge points towards where the lift goes (that is a force that 'pulls' the wing upward).
Also, the bit that hits the air first is called the leading edge, and the other end is called the trailing end. To ensure easy airflow around your wing, the leading edge is usually thicker and rounded, while the trailing edge... trails to nothing. Located rougly 25-30% from the length of your wing (as measured from front to back) is the thickest part.
Now turn that wing 90 degrees, so that the rounded bit of the wing is now pointing forward (the direction you want the propellor to pull the aircraft = forward). What is now the back side of the propellor is hollow, while the front side is rounded.
So far the easy bit. Now for the more complicated bit.
The force called LIFT (i.e. the pulling force) is dependant on V^2 (= speed x speed). So the faster the speed, the bigger the force. But if the speed goes too fast the airflow around the wing (propellor) breaks away from the surface, and you end up with no lift whatsoever.
Without getting too technical here, the tip of the propellor goes much faster than the root (the bit closest to the shaft). Given the problem above, it is important that the speed at the tip does not get too big. To that end the angle of attack (that is the relative angle the windflow has relative to the forward edge of your aerofoil) needs to be adjusted, from pointing forward at the root of the propellor to almost at right angles to the shaft at the tip of the propellor.
The easiest way to visualise this is to take a piece of paper. Hold it vertical, the bottom touching the table in front of you and you facing the writing side of the paper. Now while holding the bottom edge of the paper in place, twist the top edge of the paper either clockwise or counterclockwise. That is the shape of your aerofoil that seems to elude you, as I understand it.
Because of the material and forces involved, the tip of the propellor is much thinner than the root (so the aerofoil goes from thin at the tip to oval/almost round at the root.
Another way of looking at it is to see your propellor as a series of differently shaped aerofoils layered one on top of the other, each aerofoil slightly differently shaped as well as at a slightly different angle.
Wishing you good luck.
p.s., been following your build log with interest, might tackle one of these things as well....