This is the strap technique I use on the Two Zip Hipster and my other cross-body bags.
This style only needs one yard of main fabric, but to make the long strap would require two yards. I haven’t found webbing I’m in love with and I like the comfort level of fabric straps. I pieced the straps on this bag and this bag and they have held up fine. It’s just like piecing binding, so you quilters will already know how to do this, but I think it’s pretty cool!
For a 1.5″ wide by 66″ long strap for a cross body bag:
Cut two pieces 6″ wide by 36″ long, straight on the grain (parallel to the selvedge).
Overlap the ends, right sides together and pin. If you are using directional fabric, you can put the tops of both pieces of fabric together, making the directional fabric right side up on both ends of the strap.
Draw a line from one corner to the other, at a 45 degree angle. Sew on that line.
Cut off the outside triangle leaving a 3/8″ seam allowance.
Press the seam open.
Fuse the entire strap with a long 6″ wide by 58″ long piece of interfacing. If you have to “piece” your interfacing, just don’t do so at the same point as the strap. This will make your strap stronger. (“Piece” is in quotes because you shouldn’t piece your interfacing, just lay it end to end or side by side.)
(You probably already know how to do this part.) Fold the whole strap in half lengthwise and press. UNFOLD and refold the raw edges to the center. Press. USE STEAM for this. Fold that in half, enclosing the raw edges.
Sew along both edges – a little more than 1/8″ from the edge. 3/16″ is about perfect. I just use the edge of my presser foot with my needle in the far right position.
That’s it! Now you can make a cross body bag without buying 2 yards of fabric!