CYOR
From SA Mafia Wiki
A CYOR, or Choose Your Own Role, is where all participants choose their own role. A CYOR game can be executed in several ways, but the trait that they all share is they all allow players to choose their character or role themselves.
Straight Choice
The most common type; this is done by sending the mod a description of the character they want to be (e.g. Superman) and the mod proceeds to think up a thematic role for them (e.g. bulletproof vigilante with a lyncher). Sample past roles have been: Dr. House; Inspector Javert; a pimp; The Death Star; Fine Swiss Chocolate; the Citizens' Advisory Council on National Space Policy; The City of Baltimore; and "ART!".
Ruckus in Ruritania is a good example.
Ship of Lost Souls is a great example.
Battle for Fortune Island is the best example.
Role Auctions
Also called Wine in Front of All or WIFOA. Each player gets a designation (scum or town), and then all choose two numbers. The object is to pick the number closest to 1 that THE LEAST AMOUNT OF PEOPLE PICK. Order will be determined as: (1) closest to 1 that only 1 person picked, until all single picks are gone; (2) closest to 1 that only 2 people picked (using the tiebreaker), until all double picks are gone; (3) closest to 1 that only 3 people picked (using the tiebreaker), until all triple picks are gone; etc. If there is a tie in the tiebreaker, they will be behind any single pick tie breakers, and I will roll dice. The final Draft Order will be published in this thread for all to see. They then choose a role; if someone in front of them has chosen it, they get vanilla instead.
SUPER CYOR
You pretty much make up whatever role you want and a corresponding character. It is then the role of the moderator to divvy teams up teams in as fair a way as possible.