Referral relationships established will significantly increase your mining rewards.
Referral rules:
Each user can only be invited once, while one user can refer as many users as he or she wants.
A user cannot invite other users until he or she receives and accepts an invitation first. To invite a friend, you shall first obtain a referral link from our Discord and then follow the guide to establish a referral relationship. 
With a referral relationship established, both sides become entitled to higher mining rewards. This means, for a referer, more referees always result in higher mining rewards. In the meanwhile, uninvited users will be automatically denied access to the Pools.
Calculation for Referral Relationships Bonuses:
     Where:
Final Staking Weight: a user's original share in the pool that includes his or her Referral Relationship Bonuses.
Staking Weight: a user's original share in the pool that dosn't include his or her Referral Relationship Bonus.
Referral Relationships Bonus: for the referee, his or her Staking Weight enjoys an extra 10% multiplier.
User N Staking Weight: Staking Weight of an referee.
Please refer to the  Handbook's Refferal Mechanism for more details.