(1) Draw the given line segment \(\over{AB}\) and mark an point M on it.
(2) With M as centre and a convenient radius, construct an arc intersecting the line segment \(\over{AB}\)at two points C and D.
(3) With C and D as centres and a radius greater than CM, construct two arcs. Let these be intersecting each other at E.
(4) Join EM. \(\over{EM}\) is perpendicular to AB