here's how i distress my straps...
dunk in water w a lil soap..waterproof straps will require over 24hrs in water..
then massage the strap while it's still wet..pull them, squeeze them, pinch them, etc..
then use some sandpaper on the sides..
dunk the wet strap in oil for a few hours..
remove, let it dry in a cool, dry place, no heat!!
apply lots of leather oil..
then mink oil...i'll usually place them under the scotching sun at this pt too..
more leather oil and mink oil..
then use kiwi natural polish for the shine..