Formal:
* Sì (pronounced "see") - This is the most common and formal way to say yes.
Informal:
* E' (pronounced "eh") - This is a very common informal way to say yes.
* Certo (pronounced "chair-toh") - This means "certainly" and is a more emphatic way of saying yes.
* S'ì (pronounced "see") - This is a more informal version of "Sì".
* S'accussì (pronounced "sa-koo-see") - This means "it's like that" and is a very colloquial way of saying yes.
Other expressions:
* A sì! (pronounced "ah see") - This is an emphatic "yes!"
* S'è veru (pronounced "seh veh-roo") - This means "it's true" and is used to confirm something.
The best way to say "yes" in Sicilian depends on the situation and the people you are talking to. If you are unsure, it is always best to use the more formal "Sì".