If you don't already have an Art For Kids Hub account, visit this page https://artforkidshub.tv/gift_card_redemptions/new
Enter your redemption code and click continue. The website will walk you through setting up your account and selecting a membership plan.
If you already have an Art For Kids Hub account, visit your dashboard billing page https://artforkidshub.tv/dashboard/billing
Then click the redeem a gift card button.
The gift card amount will be added to your balance. Anytime you have a gift card balance the website will automatically deduct from the balance before billing your card.
Troubleshooting:
If you've successfully created an account and redeemed your gift, but you're still unable to watch a lesson, all you have left to do is pick a subscription plan.
You can click any lesson to subscribe or visit this page https://artforkidshub.tv/join and choose a plan.