However, you could use a combination of letters from the word itself:
* CONS: This is short and easy to remember.
* CST: A bit more obscure, but still conveys the meaning.
Alternatively, you could use an acronym that reflects the meaning of "consistent":
* RELI: This stands for "reliable," which is a synonym for consistent.
Ultimately, the best acronym for "consistent" depends on your specific context and purpose.