Setup Wizard allow you to assign/select the trello board and lists to link with your magento store.

Trello Board

From the dropdown list select the trello board, where you want all your orders to sync. Click on "Refresh" if your trello board doesn't show up in the list

Trello Lists

You will see a list of all your order status configured in the magento store. From the dropdown select in which list the order will go to when its placed depending on the order status. So you can configure depending on order status the lists and this will sync in realtime. So if an order is in processing status it will automatically be moved to the selected list.

After the configuration is complete, click on "Complete Setup Wizard"

Info macro