From Blood on the Clocktower Wiki
The Bureaucrat gives extra votes to a player of their choice.
Each dusk, choose a player (not yourself): their vote counts as 3 votes tomorrow.
The Bureaucrat selects Evin. Tomorrow, when the first vote is being tallied, the Storyteller counts "1... 2... 3... 4-5-6... 7". The nominated player now has 7 votes for their execution, and the nomination process continues.
The Bureaucrat selects Filip. Tomorrow, Filip has a triple vote, which he uses 3 times. The next night, the Bureaucrat selects a dead player - Douglas. Tomorrow, Douglas must use his vote token to vote, but if he does, his vote counts triple.
Tips & Tricks (if you are good)
Choose living players (not the butler)
Find someone that you trust / is confirmed
Watch how they vote
Ask the town to help you choose
Be super careful on final night… maybe get exiled
Tell the group who you picked
Lie about who you picked and watch the behavior of the bogus player
Double up with the Thief
Tips & Tricks (if you are evil)
Choose evil players…. Mostly
Choose good players until the perfect moment
Choose evil on the final day
Choose dead evil players, if you can justify it
Amazing Bureaucrat Stories