After PageSpeed Insights analyser, the recommendation is:
Leverage browser caching
The definition of an expiration date or a maximum age in the HTTP headers for static resources instructs the browser to load previously downloaded resources from local disk rather than over the network.
Enjoy the browser cache for the following features that can be cached:
http://maps.googleapis.com/...pi/js?v=3.exp&libraries=places&ver=4.5.2 (30 minutes)
http://js.ptengine.com/pta.js (60 minutes)
http://js.ptengine.com/pts.js (60 minutes)
http://js.ptengine.jp/586be221.js (60 minutes)
http://img.youtube.com/vi/rN_TClWUd24/0.jpg (2 hours)
http://www.google-analytics.com/analytics.js (2 hours)
https://img.youtube.com/vi/rN_TClWUd24/1.jpg (2 hours)How I setup this?