I sew it to the back and pull it to the front. I generally use the Roxanne basting glue to stick it in place. Then I use a decorative stitch to attach it to the front. Does it always hit the line perfectly on the back? No - but I plan my thread color so it is the least obtrusive if there is a miss. Plus the decorative stitch makes it look like a planned feature.
When it matters where the seam lands, I first set my stitch length to 5 and do a basting stitch all the way around so I can make adjustments along the way.