Dear Dog:
Yes, your butt is very cute, here's a scratch, but I want to pet your head now! OK, yes I see your butt, there it is! Now, SIT so I can scratch your head...
...Ok, very nice attempt, but you're sitting backwards. Your butt should not be in the air with your head on the ground. Very cute.
Love,
The part-owner of a wiggly little Boxer.