Click below to view the tutorial for adding a mitered contrast band to a tablecloth. The first step for me was putting the baby in the Baby Bjorn (yes, it is possible to sew that way) and getting my toddler to take a nap!
When pinning, leave yourself a 1/2 seam allowance from the edge of the center piece of fabric and start sewing there to allow room to stitch the band on the short side (this will make sense later if it doesn't right now, but you want the stitches meeting at a right angle, not running on top of each other in the corner).
2. Stitch the long side with a 1/2 inch seam allowance, ending 1/2 inch before the end of the center piece to once again accommodate stitching the band along the short side.
3. Now the fun part. Make a 14" (or whatever your band width is) fold at the corner, so you are taking up 28" of fabric total in the corner. This extra fabric will form the mitered corner. Pin the rest of the length of your band along the short side of the center piece, right sides together again.
You'll be starting this seam 1/2" from the edge as shown below so that the stitching lines meet up neatly in the corner.
4. Stitch the seam at the short end of the tablecloth.
Hopefully these two stitching lines meet up neatly in the corner as shown below (I used red thread so it shows more easily).
5. Now we're going to stitch the mitered corner out of the folded fabric. To do this, lay the extra fabric out neatly, right sides together, matching the edges. To do this requires bringing the seams at the short and long sides of the cloth together making a point of the center piece at the corner as shown below. Using a straight-edge of some kind draw a lstitching ine from the corner of the center piece, where the two seams meet to the outer corner of the band. Pin along this line.
6. Now stitch along the line. Your resulting seam will look like this on the wrong side:
Trim the extra from this mitered seam and press the seams.
7. Repeat the steps above with the second length of band fabric, sewing the seams along the long and short ends and forming the miter in the corner with the folded fabric. You will now have the band stitched all the way around the center piece of your tablecloth with two mitered corners and two un-seamed corners, with the extra fabric allowance as pictured below:
8. Now you'll form the miter at the remaining two corners with the extra fabric allowance. Start by folding the tablecloth at one of these corners so the seams at the short and long ends meet...
...and the fabric allowance is laid out right sides together with edges aligned as pictured below from a couple angles. This is the same type of fold you made to form the miter with the folded fabric at the other corners.
Measure this allowance 14" (or whatever your width) from the corner of the center piece of your tablecloth.
Using a straight edge, draw a stitching line from the corner of the center piece to the edge of the band at the 14" mark.
Pin along this line.
9. Stitch along the line to form the mitered corner. Your finished seam will look like this on the wrong side:
All three seams (short side, long side and miter) should meet neatly in the corner:
Trim the extra fabric from the mitered seam. Press.