Just go to the members desk at Costco
The customer service desk is combined with the return desk (where you return items). The regular size door, to the left of the two large entrance and exit bay doors, leads to the customer service/return desk.
Go to the entrance and they will tell you were to go.
Go in the door to the left and go to the customer service desk. Its quick. Even if you do it online you still have to go to the desk to get your picture taken.
You can visit the store and sign up.
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