Watch Dogs

This requires you to get tailed 5 times by other players. Unfortunately you are at the mercy of Ubisoft servers for this and there's little you can do. You have to hope when another player as selected Online Tailing that they get put in your game. There is no notification as to when you are being tailed unless you profile the person who is tailing you. There is also no way to track how many times you've been tailed, unless you look at your players met list on your PlayStation system and spot a tailing that you didn't initiate yourself.

If you find yourself not being able to get able to receive any, there is a way to fix it (if you want to call it that). You have to turn off online invasions and reset your notoriety and go back to free roam and then go back in and turn it on again. The downside to this is that you will lose all your acquired skills and progress towards them. Once you get your trophy, build it back up and have fun online.

1. In free roam, go into options and then online and disable "Online Invasions".
2. Go back to the game so you see the white emblem on the left side of the screen notifying you that the game is saving.
3. Go back to "Online Invasions" and switch it back on.
4. Go back to free roam and do nothing for about 10-20 minutes and then check your recent players met to see if anyone has joined you. If you're good enough, you will be able to spot people coming into your game. If you spot someone suspicious, try pausing the game and if the background is moving on the pause screen, someone is in your game. Also, if someone is in your game, you will not be able to accept new missions or fast travel and will see the silver profile saving icon after a successful tail by another fixer.

I did the above method each time someone had tailed me. Do not have your phone out profiling anyone! Credit to G4MERZLIFE for confirming the Steps.

A couple quick points. If you look at your players met list and see someone did a tail on you, it doesn't mean they successfully tailed you. All it means is that they selected Online Tailing from the menu and entered your game. They could have quit out right away. Also, if you see a player within the past 10 minutes, don't do anything like turn off/on online invasions in the options menu or shut off the game. They could still be trying to tail you, give them time.

As long as the other player profiles you and starts the observe process, it doesn't matter if you spot him and kill him. Just as long as the observation process began.