Pockets can be tricky sometimes. You can take the time to cut perfectly but when trying to fold the excess seam allowance for rounded or curved corners, an angular edge can sometimes result no matter how detailed or careful you press.
A long time ago I learned a trick for stitching rounded pockets which helps to eliminate the angular-ness of the edges. Recreating the Pocket step from the recent Ice Cream Dress pattern(by Oliver + S) that I made for SweetPea, I have made a simple tutorial to share the trick with you, too!
Starting with Step 2 of the Ice Cream Dress pattern, you will baste as instructed, creating your fold line for the pocket edge.
The extra step is to baste again inside the seam allowance about 1/8 inch from the original basting line. Begin just outside the curve on the straight edge. In this case I basted a second line for each curvature, starting just before and stopping just beyond the curved corners. Next, trim your seam allowance to within 1/8 inch from your newly basted lines (1/4 inch from your basted fold line). If you are making a rounded pocket, you will start your extra basting step at the beginning of the curve continuing around.
Using your long threads from the second basting lines around the curvatures, gently and very slightly pull a soft gather. Doing this will automatically bring the pocket corner into a smooth edge.
The basting stitches you see along the outside edge in the photo above were created in Step 2 as a folding guide for the pocket edge - use this basting line to fold the seam allowance in as you press. Once you stitch the pocket in place, you can easily remove the basting stitches.
Pin the pocket in place and slowly, carefully edgestitch it to the garment as instructed. I like to sew slowly around the corners, one stitch at a time, lifting the presser foot and turning the corners in between each stitch. This helps to keep the top-stitching line equidistant to the pocket edge.