The plugin W3 Total Cache settings are more than a little complicated to me.
Here is a good article explaining in detail how to set the W3 total cache plugin.
Both the free and the paid versions of the plugin are explained.
Considerations when using this caching plugin with a cdn are offered.
How To Make Your Website Load Faster Using W3 Total Cache Plugin? Learn the steps in this detailed post covering all the steps for optimal setting of the plugin.