Help:Account

From Shopify Wiki

Adding staff members

If you have people besides yourself working on your shop, you should create accounts for each of them. Staff members can do anything the account holder can do, with the exception of viewing or changing the credit card information associated with the account.

Adding a credit card

Before you can start selling products, you will need to submit information for a credit card to be billed for Shopify's fees. To set up a payment gateway, use the Preferences section. Shopify accepts Visa, Mastercard and Amex for monthly payments. All credit card data is transmitted securely regardless of the type of the account (Trial, Basic, Professional etc.).