Assassin's Creed II/Sequence 2: Escape Plans

When the sequence starts you'll be notorious, meaning the guards are on high alert and will attack on sight. At this point, you'll be able to find glyphs on some buildings. Rebecca will mark any landmarks you come across accordingly, and you can look in the Locations section of your Database to see which ones have glyphs.

Fitting in
When you get the chance, walk into the center of one of the groups of girls on either side of Paola. You should see a white circle around the group, and the girls will turn gray and the minimap will be ringed with green. This means you're anonymous, and guards won't bother you. When she leaves, follow Paola around the building. When she walks toward the first group of guards, go blend in with the group standing to their left to wait for her to get past them. If the guards are alerted by you, you'll fail the memory and have to start over. Keep following her as she walks, by going from group to group. You can also blend with moving groups that are going the same way as you. Eventually you'll get back around to the other side of La Rosa Colta.
 * Memory start: Knock on the front door of La Rosa Colta in the San Marco District.
 * Rewards: Blend skill, Courtesans now available

Next you'll learn to pick pockets (although you've been able to do it from the beginning of the game). Steal from one of the nearby girls, then walk out into the street. You'll need to steal from five people. Hold the legs button while you're walking around and bump into people to steal from them. When you've picked someone's pocket, walk away or they may accost you. You'll be blocked from leaving the immediate area, so you'll have to make do with whoever walks through the alley behind La Rosa Colta. When you've stolen from five people the memory will automatically end.

Ace up my sleeve
Head back to Leonardo's workshop to the west, just north of your house. If there are too many guards around, blend in with a group that's headed the way you want to go. When you get to Leonardo, he'll decrypt your Codex page and repair your hidden blade. From now on, Leonardo will decode any Codex pages for you, which will sometimes result in an upgrade for your equipment. You'll also get another block on your synchronization bar for every four Codex pages you bring him. Afterward, you'll need to save Leonardo from a rough interrogation by running up behind the guard kicking him, and pressing the armed hand button with the hidden blade equipped. This will assassinate the guard.
 * Memory start: Speak to Paola at the back of La Rosa Colta.
 * Reward: 200ƒ, Hidden Blade, Assassination skill

Pick up the dead man by standing over him and pressing the unarmed hand button. Walk him back around into Leonardo's workshop and drop him in the white marker with the same unarmed hand button.

Judge, jury, executioner
It's time to perform your first assassination and take out Uberto Alberti, the Gonfaloniere di Giustizia, at Santa Croce. Head to the southeast and climb the roof of the building next to Santa Croce, where you'll find the white marker to start a cut scene showing Uberto and Lorenzo walking into the cloister. Take a leap of faith off the post next to you and join a group walking in the direction you need to go to escape the notice of the guards. When you get to the entrance, you'll see it's guarded by two brutes, so head around the corner and hire the courtesans there to distract them. With the guards distracted, walk into the cloister and join a group in the courtyard. If you don't know which guy your target is, hold the head button for eagle vision, and he'll be the one colored yellow. Walk up to him with the hidden blade equipped and assassinate him.
 * Memory start: Knock on the front door of La Rosa Colta.
 * Reward: 400ƒ, letter from Uberto Alberti, conspiracy documents

After the death scene, look behind you toward where you entered the cloister, and start free running at the boxes with white sheets over them. This will take you up to the roof, where you can continue south over some hanging boards to the next rooftop and then down into the street after you've gotten out of the search radius. Blend in with the crowd or enter a hay cart to become incognito and end the memory.

Laying low
You can reduce your notoriety by tearing down posters, bribing heralds or killing officials. They're all marked on your map in whichever district you happen to be in, regardless of whether you've synchronized any viewpoints nearby. Your notoriety is measured by the ring around your status indicator in the top left of the screen. Posters will reduce 25% of the ring and cost nothing to tear down, bribing heralds will reduce 50% of the meter and costs 500ƒ, and killing an official will reduce it by 75% and also costs nothing. Whichever way you choose, when your notoriety is back at zero, you'll lose the red status indicator showing the guards are on high alert. Doing bad things in town, such as stealing or killing guards will slowly increase your notoriety. When it gets completely full again, you'll be notorious and have to deplete the entire notoriety bar, so it pays to tear down a poster here or bribe a herald there whenever your notoriety gets above 50%. Officials will only be available when you're fully notorious.
 * Memory start: Knock on the front door of La Rosa Colta.
 * Reward: 200ƒ

Arrivederci

 * Memory start: Knock on the front door of La Rosa Colta.
 * Reward: Simply run through the city hitting a couple white markers at checkpoints along the way. At the city gate use a group of courtesans to distract the guards or kill them all to get past them. Eventually you'll be led out along a road and Sequence 2 will be complete.