Adding your card to Apple Pay is simple!
Open the Stocard app, head to the "Pay" tab and tap the “Add to Apple Wallet” button. For the Apple Watch, open the Stocard app on your iPhone, head to the "Pay" tab and open the payment card settings (this can be done by clicking on the three dots in the top right corner). Now tap the “Add to Apple Wallet” button and select your Apple Watch.
Find out how to make Stocard your default card in Apple Pay here: