Mafia: Definitive Edition is not like other modern open-world games out there. During the main campaign, you jump from one mission to another continuously, giving you no chance to roam around the beautiful open-world or change the way your character looks. For players who are interested to free roam, there is a different game mode altogether for it, Free Ride.
Fortunately, the free-roam mode does offer a way to change your clothes and outfits. If you want to change your character’s outfit, you first need to go to the main menu and select the Free Ride option. Do note that you need to finish the mission “An Offer You Can’t Refuse” before you can unlock Free Ride.
Once you are in the Free Ride mode you need to go to Saleri’s bar. Head to the back room of the bar near the pool table, and you will find a staircase in the adjacent room. Climb up the staircase and there will be a door on the left. Unlock the door and you will find a wardrobe with which you can interact with to change your outfits.
If you want to unlock new costumes, there are multiple ways to do so. Progressing in the game’s main campaign will automatically unlock new costumes. Likewise, if you finish the Phone Booth Challenges available in the Free Ride mode, you will be able to unlock more costumes. Lastly, some of the costumes can be found by exploring the game’s open world.