Steam- Epic-
After downloading the mod, extract the contents and move the mod .pak file into PAYDAY3/Content/Paks/~mods. Create the folder if necessary.
To load the mod there are two different ways. Option 1 is the preferred way but if you cannot get this to work then try option 2.
Option 1: UE4SS / AllowPaksMod
Download UE4SS for Payday 3 and make sure AllowPaksMod is enabled.
Make sure you dont have -fileopenlog in the launch options
If Logic Mod is needed: Download this version of the Logic Mod Loader and place it in your ~mods folder
Option 2: -FileOpenLog
Add the launch option to the game.