How to crack the back of my iPhone but not the front?

Ok I'm a dude and I think coloring the back of your iPhone if its cracked looks sick. I have a clear case too. Is there a way I can crack the back without cracking the front, camera lense or anything else?

Hit the back bottom left corner with the handle of a screw driver

Deliberately breaking an expensive item is beyond me… Never bothered to figure out now and quite honestly never expected to be asked. You must be the only person who wants a broken iPhone.

Tap the back lightly with a hammer

Hipsters at their finest. Smh