Choose a simple quilt square design, one that is primarily composed of straight lines. Remember that small details will be lost if the quilt is to be viewed from afar.
Draw out the pattern on graph paper. A ratio of one inch per foot works well in designing the square. The pattern can then be enlarged for printing or used in creating a grid directly on a wall.
Print out the pattern and transfer it to plywood or a wall. If you are painting without a pattern, create a grid on the wall and sketch out the pattern lightly with thinned out paint or thick pens
Apply primer to the area.
Fill in the pattern with latex paint.
Mount a completed plywood square to the exterior wall. Hang the barn quilt so the bottom of the design is at least two feet above the ground.