Complete these in the following order to decrease the difficulty of each major assassination and lower the time needed to complete the game:

1. Visit Assassin's Guild.
2. Scan the city by first climbing all of the view points.
3. Rescue all citizens from the thugs.
4. Complete all of the informant's missions
5. Pickpocket the shysters in all of the pickpocket missions
6. Go back to the Assassin's Guild and get ready for the major assassination mission.