This is a good tip for Speeding up & Optimizing website performances
1. Do this step once, either if the site is still on development or already in production
INFO: What is Leverage browser caching?
Page load times can be significantly improved by asking visitors to save and reuse the files included in your website.
General guidelines for setting expiries:
2. Do this step when the website has been completed and it's in production
This is the ideal configuration for Speed & Optimized performances
3. At this point your website should be quite fast, between 80% and 95%