Construction of a Rhombus
1. Construct a line segment.
2. Draw two circles, one using an endpoint of the segment as a center and the other endpoint as a point on the circle arc and vice-versa,
3. Mark the intersection of the circles and connect one endpoint to the intersection.
4. Construct a line parallel to the new segment using the other endpoint not used in the old segment.
5. Mark the intersection of the third line and the circle arc.
6. Construct a segment between the new intersection and the second segment.