Cut out your straps from both your fabric of choice and some durable interfacing or canvas. The width of your straps should be twice as wide as you want them. The length of course is up to you!
iron the edges of your straps in towards the center. If you cut your fabric right, the raw edges should meet in the middle. I cut mine a little too narrow so I'm only folding them over part of the way, but they still will be pretty sturdy straps.
Step 3 Once you iron over the edges, fold your strap in half and iron it down again. Your strap is now 4 layers of fabric and interfacing thick. Pin this fold down to keep it together while you take your straps to the sewing machine!
Step 4 Sew your straps closed, and then top-stitch along the fold as well to make it look more uniform. If you want, you can sew a couple more lines down the center of your strap to really hold it together and make it stronger yet.