If you want to set up recurring payments and integrate with s2Member, everything will be handled directly through JVZoo when you set up your product. You will see the s2Member integration on the right side of the screen under advanced features and then external program integration.
You will also want to check the s2Member integration documentation supplied by s2Member to ensure you have things properly setup. Sometimes programming changes are made on either the JVZoo side or the membership side so it is necessary to check the third party software for changes.