To obtain rounded shapes in a design, use quarter and three-quarter cross-stitches.
On linen and even-weave fabrics, a quarter cross-stitch extends from the corner to the center intersection of the threads. To make quarter cross-stitches on Aida cloth, estimate the center of the square.
A three-quarter cross-stitch combines a quarter cross-stitch with a half cross-stitch. Both stitches may slant in any direction.