To redeem the "American Express 6mo 1 USD United States of America Payment Card" after purchasing, the user would typically follow these steps:

1. Receive the Card Details: After purchasing, the user will receive the card details, which might include the card number, expiration date, CVV, and possibly a redemption code. This information could be delivered via email or directly on the website where the purchase was made.

2. Activate the Card (if necessary): Depending on the provider, the card may need to be activated. Instructions for activation will usually be provided along with the card details. This might involve visiting a specific website or calling a customer service number.

3. Use the Card: Once the card is activated (if necessary), the user can use it for online purchases or other transactions where American Express is accepted. They would simply enter the card details at the checkout page of any merchant.

4. Monitor Usage: Since this is a 6-month card with a balance of 1 USD, the user should be aware of the balance and the expiration period. The card can typically be used within the United States, as specified by the "United States of America Payment Card" description.