In Agma.io if you go inside of the shop and click the [Free Rewards] Invite Friends button. It will take you to a page where you can copy a link and send it too your friends.If they accept and create/register an account you will get a referral. You can use referrals to get rewards such as minions,money, and even gold membership for a few days.You can first get a reward at 5 referrals. You can share the link anywhere as long as you do it legally. The link is https://agma.io/?ref=1192157191.