Technique: Matching Seams

It can be tricky to get seams to meet, like the seams 
between the ruffles of this dress when the front and back 
are sewn together.  This is how I like to do it.

Hold the fabrics right sides together, near the seam to be matched.
Fold the edges back enough to see both sides.

The key is to make sure the seams line up at the point where
the seam will actually be sewn, not just at the edges.  This
shows two seams meeting at my 5/8" seam allowance.  You may
wish to pin your fabrics together at this point.  I usually hold 
them firmly so they don't shift.

Set your machine to a basting stitch.

Baste across the seam.

Sew a little before and after the seam intersection.  You want to
make sure you sew enough to hold the fabric together well, but not 
too much in case you have to remove the basting stitches.

Check and make sure the seams match.  If they do, sew
the seam as you normally would.  If not, remove
the basting stitches and try again.