This spoiler-free chapter of the guide to The Last of Us 2 has a walkthrough for Ellie and Dina's patrol sequence.
Follow Dina until you get to the building. Leave your mount and continue on foot. Follow Dina and watch the panorama from the balcony together.
After a little flirting, follow Dina until you reach the room with the notebook. Sign up for the patrol list. You should also search the next room for some crafting materials. Then go back to the horses and follow Dina.
The road to the second outpost and the fight against the infected
While following Dina, you will come across abandoned buildings. You can search them for some valuable materials and supplements to help you develop your character.
On the way to the outpost, you will come across a dead moose. Follow the bloody trail and enter the building through a window. There is an infected in the area, so try to be quiet and eliminate him using a knife. In TloU2, Ellie's knife doesn't break after using it a few times, so you can use it endlessly to eliminate enemies quietly.
After killing the enemy, approach the door to enter the next room. Ellie automatically picks up the bottle - throw it at the enemy and then use the knife.
Search the room, then jump out the window - you will come across another two runners. Approach the one on the right and kill it quietly. Dina will automatically kill the enemy on the left. Then climb through a window into the red building and, and eliminate more infected together with Dina.
Search the building, then go outside and help Dina jump on the truck. Join her and jump to the other side. Crawl under another truck - you will be caught by a runner.
After the cut-scene, climb on the truck and the go through a hole into the building. Inside, you can collect a few materials and open a safe (07-20-13). When you are ready to continue, go through the passage indicated above - the floor will collapse.
At the bottom, you will encounter clickers - these enemies are much more dangerous than runners. You cannot fight them in melee combat (without using special weapons such as a crowbar, axe, etc.) and these enemies are much more vigilant which makes stealth a challenge. When you are close to a clicker, slow down when approaching the enemy and wait for the moment to get rid of it quietly. You can also use a flashlight when fighting with the infected - they won't react to light but to sound. They can also become hostile when they see you directly.
Search the area, then, with Dina's help, pick up the case and move on. Inside, you will find Molotov cocktails - you can now craft them. They are very useful in combat - try to always have at least one cocktail ready for a battle. Now jump through the window into a large room occupied by a group of infected. There are a few runners and one clicker patrolling the area, the best way to eliminate the whole group is to act quietly.
Pull out the cable stuck under the cabinet and throw it so that the rope falls to the other side of the metal scaffolding.
Climb up the line and descend with Dina from the building. Then get on your horse. Soon, Dina will ride too far forward - she will disappear from your sight. Stick to the right side and ride forward. After a while, you will encounter the woman again. Ellie and Dina will reach the building.
Break the window and enter the room. As you move on, you will come across a lot of stocks that you can pick up. Search the area and then go to the generator - activate it. You can use the nearby workbench to upgrade one of the weapons.
You must now reach the suspicious bookshelf and move it to unlock a hidden passage.
When you go downstairs, you will reach a basement with a variety of herbs. Go to the jar and pull the joints out of them - watch the cut-scene.