Football Manager tactics usually have a fmf extension, we just need to move these files to the tactics folder in the game’s installation folder on your computer.
Go to the following location in file explorer:
C:\Users\YOUR USER NAME\Documents\Sports Interactive\Football Manager 20**\tactics
Copy your fmf files here.
Once back in your game, go to your tactics screen and choose ‘load’ from the the tactics dropdown menu. This should point to your tactics folder location by defaut. Simply choose one of your tactics to load it into your save.