Sometimes it can be useful to include a "Customers who bought this also bought..." with related products.
YWD will list all related products at the bottom of the product details page. Both the layout and the text for the related products area can be customized in Global settings.
Managing related products
From the list of products, click a product name to get its details. Scroll down and at the bottom you will see a box for 'Related products'. Click the pencil icon and you'll see a form. Move the product(s) from the left pane to the right pane and click 'Submit'. After that, YWD will automatically list the related products at the bottom of the product details.
Click the pencil icon for the 'Related products' box...
...then move the selected products to the right and save.
Relating products is a very complex operation internally. It may several seconds until YWD is done. Please be patient and avoid pressing 'Save' more than once.