Sh*t can only be used in the figurative noun form or the adjective form.
You can only use it in the none literal sence.
For instance, "That's a sh*tty picture of me" is now fine.
However the literal noun form of, "This is a picture of sh*t" is still naughty
The adjective form is also acceptable, for example, "The weather outside is sh*tty"
However the literal adjective is not appropriate, for example, "My bad diarrhea made the inside of the toilet bowl sh*tty and I had to clean it with a rag which then also became sh*tty"