how to draw a circumcircle of any scalene triangle

Draw perpendicular bisector on all the three sides.

 

Mark the intersection point of all the three perpendicular bisectors.

 

This point will be equidistant from all the three  vertices of the scalene triangle.

 

Using a compass, draw a circle, with the intersection point as the centre and the distance between the intersection point and any of the vertices as the radius (circum radius).

 

This is the circumcircle of the scalene triangle.