If you will refer the $CSS token to your friends:
15% of your friends’ rewards will be automatically sent to you whenever your friends harvest $CSS. You do not need to harvest, it’s automatically sent to you, free of gas fee. The 15% fee is calculated on top of friends farming reward!
Please see the example:
If Mark has referred Bob:
Bob has claimed 100 $CSS which in total went to his wallet.
Mark received 15% x100 CSS = 15 CSS which has been sent directly to his wallet.
Mark will only see Bob's address details on his CSS friends list when Bob makes the first deposit into the farming pool or stake.