Now you've come to creating your Promotion once all the setup has been done. From the search bar, type "Promotions" which will open up the Promotions List page. This page shows any existing promotions that have been created within Dynamics 365 Business Central.
As well as the No and Description, the list view offers some additional visibility into data parameters for each promotion as well as a Boolean field to show whether it is Enabled or not.
From here, you also have the ability to Enable and Disable the promotions without having to open the cards, plus the Copy Promotion option is available from here which will Copy the highlighted Promotion leaving this as disabled by default.
The position of the promotion in this list will determine which one is automatically applied to your Sales Order hence the 'Move Up' and 'Move Down' options in the ribbon are essential to position them in the way you desire. This is also taken into account when using multiple promotions on one order.
Finally, when you are ready to create a new promotion, this can be done by selecting New and either choosing the '+New' option to manually create a new promotion or by the 'New Promotion' option which will use "Assisted Setup" which is explained here.