Method 1: Draw an arc with B as the origin and AD as the radius, and then draw an arc with D as the origin and the length of AB as the radius. At this time, the intersection generated by two arcs is linked by a straight line between point B and intersection, and point D and intersection. (In principle, parallelograms have equal sides)

Method 2: Extend the straight line AB, with B as the origin and AB as the length? Draw an arc with this as the radius. This arc intersects the extension line at a point, and the intersection point on the right hand side is taken as point C. Since A is the origin, AB is the radius, and the arc intersection point ad is point E, measure the distance of BE with compasses, and draw another arc at point F, with point C as the origin and BE as the radius, and link CF and extend. At this point, with AB as the radius and D as the origin, draw an arc intersection with this extension line, and you can draw a parallelogram.