Step 1: Draw a line segment AB.
Step 2: With center A and any radius, draw an arc which intersect AB at C.
With center C and the same radius, draw an arc which intersects the previous arc at D.
With center D and the same radius, draw an arc which is interesting at E.
Step 3: With centers E and D and radius more than 1/2 ED draw arcs intersecting each other at F and join FA which intersect arc at G.
Step 4: With centers E and G, and radius more than half of EG, draw arcs intersecting each other at H, and join HA.