My edges are wavy:
Sometimes the borders are too long. To correct this, you must measure vertically through the centre of the quilt, then cut the two side borders that exact same length. Pin the centre, the ends and in between and ease the edges of the quilt to fit. Follow the same procedure for the horizontal measurement. This keeps your quilt square. However, the edges can still get wavy if you apply your binding incorrectly. As you sew the binding onto the quilt, pull the loose end of the binding snug. This will ease in some of the fullness at the edge of the quilt.