Unlike the rest of the onsite campaigns, products recommendation campaigns do not have the option of choosing a template. Both the design and the campaign content must be created in HTML by you.
For editing product recommendation campaings, you will need to know some basic HTML because the campaign design can be created just by using HTML. Once you will click the Edit button from CONTENT, a pop up will show up, where you have a blank space for writing your HTML. In case you want an example, on the right side of the pop up you have the EXAMPLE HTML button.

Tags Menu it shows you some dynamic tags which you can include in your campaign.

From Algorithms Tab you have the possibility to set the proper settings for the products that will appear in the recommendation campaign.

Number of products is the number of products that you want to have in your product recommendation campaign.
The products that will appear in the campaign will be automatically added after selecting the proper algorithms (maximum 3).
Available algorithms
To read more about product recommender algorithms please read this article.