Deferred payments means, that the payment is "reserved" until you manually complete the payment. To set this, select the connector in your Space/Payments/Configuration/Connectors:
The default setting is immediate. To change this, click on Edit, and change the Payment Completion to deferred.
Please note, that with some shopping carts, you will have to change the settings in your shop backend as well. When using Shopify, you only have the option to manually/automatically complete all transactions and cannot be defined for specific payment methods. To do this, go into your general Settings/Payments and change the settings in the Payment Capture: