Although Watch Dogs: Legion has an autosave system which will automatically save your progress whenever you pick up a new item, complete a misssion, or complete some other arbitary task in the game it is recommended that you know how to manually save the game as there are reports that the autosave will sometimes not trigger for whatever reason so it is best to be safe and save manually after each important event to avoid losing big chunks of progress.
In order to manually save your game in Watch Dogs: Legion you must use the fast travel feature as doing so will literally force the game to auto-save your progress. Fast travel in Watch Dogs: Legion is based on subway stations scattered around the city. They will become marked on your map with a London Underground logo as soon as you enter a borough for the first time. Then simply visit the subway station to unlock it. To use the subway station as a fast travel point you just need to launch the world map and select one of the fast travel points you have already unlocked. When you then hold down the key confirming your decision you will be instantaneously taken to the subway station you chose.
Whenever you finish a session in Watch Dogs: Legion it is recommended that before you quit the game you go to the nearest subway station and just use the fast travel feature so you are safe in the knowledge that you have saved your progress in the game. Ubisoft felt that players would abuse a manual save function in order to get back dead operatives if one was implimented into the game so they decided to leave it out. When you look at things from that context you realise the creators of the game made the correct decision.
Take a look at our How to Fix Errors and Bugs guide to find out what to do when your game starts misbehaving and not working correctly.
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