Discovery
Search the house and eventually you will find what you are looking for. When you regain control of Ezio, jump right into the streets and walk through the main gate. Kill the enemies here (this is a good time to do the bonus objective). Once you've completed your bonus objective, you can actually head straight for your target, completely bypassing all of the enemies here. Run for the target, climb the building and drop down next to him. You don't actually have to "assassinate" him.
The Exchange
First go to the Assassin HQ and start this mission, then head to the next checkpoint to meet up with your Assassins. After that, climb the wall and meet up for the exchange. Then you want to turn around and climb the tower to the top to save Sofia but when you get to the top, you discover your princess is in another castle so jump off of the building and parachute down. If you keep an eye below you, you should see a zipline that you can fall onto for a trophy or achievement, however this will slow you down causing Sofia to lose health which may cost you the bonus objective. Either way, hurry over to her and interact with her to free her.
There isn't any fighting or sneaking necessary. The only two constrictions are that you need to reach the top of the tower in under two minutes (can probably do it in under one) and that you need to save Sofia before she runs out of health which should not be overly difficult since you can literally go as the eagle flies.
End of the Road
To kill guards, crash into them. If you wind up more (come in at a steeper angle) then you will deel more damage. So keep bouncing off of them to get rid of them. When you end up with carriages on either side, just keep bouncing back and forth between them to maximize damage. Remember to stay on the grass because your carriage takes damage on rocks.
After you deal with this two carriages, you'll end up using your parachute. In this section, you need to take out the guards on horseback that are harrassing Sofias carriage. You can push forward or back to adjust speed, press left or right to dodge obstacles and use the strike button to assassinate the guards. You need to kill 20 of them to finish your bonus objective. Use medicine if you need it. Once this section ends, you'll be caught in an airborn duel with Ahmet.
At first, you can only hit the High Profile button to block his attacks but after that, you'll be able to strike him and block his attacks. After the tussle, you will finish this mission
