Just about the first thing anyone does with a compass is make triangles and hexagons.
Start with a circle. Pick a point on the circle and make a circle around it of the same radius.
Use the points of intsrsection to add more circles of the same radius.
There will be 6 points thus produced; from them, one can make trangles and hexagons inside the circle.
By making a diameter that goes through a pair of secondary-circle intersections, and using the points where tha diameter cuts the original circle, one may add a second set of 6 points, and from those, make a dodecagon.
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