If you do not have an account with us, head to signup where you will see the option to enter your code, as shown below:
To create a new account with a gift subscription, go to www.toucanbox.com > Gift Card > Redeem Gift Card
If you already have an account with us and you wish to apply the code onto your existing subscription, login to your account and head to Manage Subscriptions. You will see your child's subscription listed, along with an option to "Redeem gift or prepay code for this child's subscription". As displayed here: