Best way of introducing S-Builder to your affiliate is through team contest/reward.
You can offer 50% refund for their Standing Order on S-Builder co-op as a reward for achieving EA2 rank or for sponsoring a certain number of PSA's.
You already introduced S-Builder co-op and help your affiliates to earn a 2 badge (S-Builder Co-op and Standing Order) at the same time you are building your team by motivating and/or making active affiliates.