If a Mafia member is on trial and most likely will be voted guilty, it may not make much sense to vote innocent. Doing so will expose you as Mafia immediately, especially if you are one of very few people to vote innocent.
Likewise, being the only one to not vote a confirmed Mafia to trial can be almost as bad as voting innocent.
Night Meeting/Action[]
It is highly recommended to AVOID say each others names at night on the chance that there may be Spy in the game who could be listening to Mafia chat.
In some cases, using false names may causes confusion among the Town people (see: WIFOM).
With some limited exceptions, it does not typically make sense to frame, blackmail, investigate, or block the person that the Mafia is about to kill.
One advanced tactic if the Mafia has a Janitor is this: If a Mafia member is sure to be killed at night, have the Janitor target that Mafia member. This will make it so that the Town doesn't see his role and thus leaving them with no information.
If you know a Mafia member is in jail and will be executed by the Jailor.
A Consort can block the Jailor so he can't do the execution.
A Janitor can clean the Mafia member so no one will know if he really was Mafia or what role he was.
Other[]
Try to avoid killing players the Neutrals too early in the game, let them cause confusion in the Town and don't waste kills on them.
If figured out who the Neutral Killer is, and they have outlived their usefulness or is starting to be a danger to the Mafia. Make the Godfather/Mafioso write a Death Note saying who it is.
Consiglieres should be careful about revealing themselves as Investigators, make sure it's possible for there to be more Investigators, and that people don't happen to have died in the same order as your clues.