It's possible to import or create Product Catalogues, Feeds, or Sets on The Next Ad. If you want to do this, you can read this article.
Now that you have your catalogue/feed/set created or imported, you can proceed to the next step, which is using these assets in a campaign. The first step to take is to create a Product audience, so that you have a target audience to which the products will be shown.
To create one, go to the left-hand side of your screen, and select Audiences > Source audiences. The audience dashboard contains all the audiences you have created or imported onto The Next Ad.
Now go to the right-hand side of the screen, click on +Create new audience and select Product audience.
Now you will see this popup:
(1) Enter a Name for your product audience.
(2) Select a Product set from the drop-down menu. You can also see the preview and the settings of your chosen set.
(3) Now you will set the core of the audience: who you will include so that they see your products. You can choose people who viewed, added to cart or purchased your product. Then specify the time window for that specific conversion (e.g. Include people who viewed product > in the last 30 days). Another option is to Exclude people from your audience.
Congratulations, you can now create a product audience and proceed with your product catalogue sales campaign!