This is my newest Apron. It's inspired from a vintage 1940's style apron, with straps that cross in the back.
I sewed mine so that it is completely adjustable. I stitched the back straps to the waist ties, making them very long.
The aprons of the 40s & 50s had back straps that were often sewn directly into the waistband. To make mine an adjustable apron, I added "belt" loops to the waistband where the waist ties would have been stitched together. This is so that my straps can go thru it.