With the Google Ads script: nothing to set up. On its first run the script makes two conversion actions in your account, "ResultsAiX ADs - Lead" and "ResultsAiX ADs - Sale", and from then on every hour it sends the leads and sales traced to a Google ad click (the gclid), with their value.
With the direct connection: Google Ads tab, "Send your leads and sales back to Google", press Set them up for me and ADs makes the two conversion actions (or choose existing ones). From then on every lead and sale traced to a Google ad is sent every hour through Google's Data Manager API.
Optional, for the script: your script already sends the leads and sales that came from a Google ad click. Under "Send your customer lists to Google", "Optional: leads and sales matched by email" gives Google a file of the rest, with scrambled email addresses, which it collects from your site once a day (Tools, Data manager, Connect product, HTTPS, Conversions). The file is protected with the username and password shown.
Sales are de-duplicated, refunds are never sent as sales, and email addresses are scrambled (SHA-256) before they leave your site. Make sure auto-tagging is on in Google Ads, so every click carries the gclid that ties a sale to its ad.