This method is guaranteed to work. This is a luck game, as evidenced by the pie of every player being around 50% in wins and losses. Thereby, you have to defeat lady luck at her own game. I'm thereby introducing the one website you can never be wrong with - random.org.
With the power of the Random Number Generator you're super likely to find mafia, since the Gods are always right. Believe in your number, succeed in gaining a "read", and then make up reasons and spam harder than Jeff.
I'll now provide an in-depth strategy to win the game based on the RNG method, but you'll have to prerequisite some stuff:
As soon as the game starts, you'll have to not talk for a while. If you want, make up a reason and insufficiently participate - this works both for town and mafia. Say you're back and pretend you reread, and then start asking your random number pointless questions and then say that you used your investigative abilities to find them.
Good excuses for ISP'ing include clipping your nails, YouTube, and eating.
This method is guaranteed to give you a trophy in three rounds at best. For an in-depth strategy at how to win competitive games, follow the advice written on my next guide involving the smart usage of alts, intentional but not apparent gamethrowing, as well as lurking as town.