You earn a referral commission equal to 5% of the final NFT mint price paid when another person successfully completes a new mint with your referral attached. Secondary-market purchases do not qualify.
For example, if an NFT is minted for 1 ETH using your referral link, you will receive 0.05 ETH. If a coupon or other discount reduces the mint price, the referral commission is calculated from the discounted price actually paid.
Ethereum network gas fees are separate and are not included when calculating the referral commission. Referral commissions are paid in ETH to the referring wallet and recorded on-chain when the mint is completed.