Please be aware that this graphical mod DOES NOT go into the "Documents\Sports Interactive\Football Manager 2016" folder as normal graphics do (kits, logos, faces and so on). It will not work/have any affect if extracted here.
Instead extract the whole folder "Debski's World of Hairstyles for FM16 v1.0" into the following directory on your computer:
"[YOUR FM GAME FOLDER]\data\facegen\hair"
Default place to look for this folder is "C:\Program Files (x86)\Steam\steamapps\common\Football Manager 2016"
For Mac users, the FM GAME FOLDER should be here:
[username] > library > Application support > Steam > steamapps > common > football manager 2016
The above mentioned folder (hair) should now contain minimum 6 folders. The "afro", "asian", "euro", "hispanic" and "mixed_race" standard folders by SI, alongside with your new "Debski's World of Hairstyles for FM16 v1.0" and eventually other custom graphics you might have installed.
Open up FM16, go into preferences > interface and click the "Clear Cache" button.
When done, close the game. Run again, and everything should be up and running.
Files are save-game compatible, meaning you don't have to start a new game for them to make effect.