I chopped the metal buckles off of the shoulder straps, I cut them to a taper so that they look like they are meant to be that way. I softened the leather up by pulling it back and forth over a rounded edge, in my case the wooden rail on the back of my daughters' high chair. That got the stiff leather more supple and I rubbed in some nikwax product or other. They are great bags and you don't really need to waterproof the sack, if you are worried about water than throw a dry bag inside.
