In Nigeria, selling Amazon cards worth 20 can be a viable option. Firstly, it's essential to find a reliable platform or community where potential buyers are present. This could be through online marketplaces dedicated to such transactions or local groups focused on digital currency exchanges.

When advertising the Amazon card for sale, clearly state the value and provide detailed information about how the card can be redeemed. Include instructions on how to access the Amazon services with the card. This helps potential buyers understand the usability and makes the selling process smoother.

Another crucial aspect is to ensure security during the transaction. Use secure payment methods that protect both the seller and the buyer. For example, consider using escrow services if available in the relevant platforms. This safeguards against fraud and ensures that the money is transferred only when the card has been successfully verified and redeemed by the buyer.