Referring people is by promoting people to join SMG community and you can do that by sharing them a link to the website (with your code (it's on your user control panel) if you're aiming to get the scout rank) and once people go on the website and sign up, they can either choose to put the name of the person that helped them or referred to them to the website.
By referring others, not only are you working your way towards earning the scout rank, but also aiming towards helping the smg community get more attention and wider amount of members and audience
For more information on referring (and the scout rank), here's the link to the help page:
https://smgclan.net/misc.php?action=help&hid=9
*REMEMBER* If you have any questions, refer to the help page:
https://smgclan.net/misc.php?action=help
You can also ask anyone for help (if the help page doesn't help), most of all, the staff members (since they're more of an expert on these kinds of things)