Hello again Dr,
To circumscribe a square around a circle draw two diameters perpendicular to each other( one horizontal - one vertical to simplify exp.) Where the four points meet the circle draw two horiz and two vert tangents. Intersections of tangents define the square.
Also do not call this "square the circle" which is the name of a problem from classical antiquity to construct a square with the same area as a given circle using straight edge and compass only. This is impossible.