First on your e-commerce site
Like all software added to your site, you must download the module of your feed manager . You must check that it is compatible with the version of your site (ex: Prestashop 1.6). Then, there are operations specific to the module to be configured (eg: identification code to be retrieved from your manager) and the setting up of your preferences in the module (eg: display).
Then on the platform of your feed manager
This is where you set up your flow, and optimize it using mapping rules, category rules, and various management rules. An e-commerce feed management solution like that of Sellermania allows you to preview the feed before distributing it, to have an overview of errors to correct them upstream. For example, you can do a test on a single product, and make sure that your feed is correctly configured, before broadcasting your entire feed.