There are a couple of decisions to be made when you are presenting your payment UI. You have the choice between a payment menu with all the payment instruments you want to offer, or with a single available payment instrument using instrument mode.
Regardless of the number of instruments available to the payer, you also need to
Redirect, the payer is sent to a Swedbank Pay page where we handle the
purchase process. The payer is redirected back to you when the purchase is
completed or if the payer aborts the purchase. The page will be styled by
Seamless View, the payer stays at your site and you initiate the
Swedbank Pay purchase module in an iframe. The purchase component will be styled
by Swedbank Pay.
Read about how you integrate them by following the links.