You have to lift your presser foot up a bit with the needle in the machine and move the fabric around the curve a tad, drop the foot, sew a few more stitches and repeat as necessary. I also press the pocket before and after top stitching.

The best thing I have to assist in top-stitching is a patch-work foot that is exactly 1/4 inch from the needle to the edge. Line up the edge of the foot with the edge of your work. Yes, you do have to stitch and turn while the needle is sunk in the fabric, but it's worth the extra care you take. Also if your stitches are creeping in, possibly you need to grade, clip and trim your seams closer to remove the bulk. Another thing for better top-stitching is to use buttonhole twist, a thicker thread that does a great job. Alternately, you can thread two threads through the needle, but I've never had good luck with that.

Mary