How do I defer parsing of Javascript to iprove performace

Please make this post a private. Thank you.

I ran GT matrix on my site http://www.dermotmurphy.com and one of the recommendations is to Defer parsing of JavaScript (See below) -

How do I go about this as I don't understand what it means?

Thanks,

Dermot

F (45)
65%
JS High
What does this mean?
323.5KiB of JavaScript is parsed during initial page load. Defer parsing JavaScript to reduce blocking of page rendering.

http://connect.facebook.net/en_US/all.js (126.4KiB)
http://www.dermotmurphy.com/wp-includes/js/jquery/jquery.js?ver=1.10.2 (83.7KiB)
http://www.dermotmurphy.com/wp-content/themes/Avada/framework/plugins/revslider/rs-plugin/js/jquery.themepunch.revolution.min.js?ver=3.7.1 (43.3KiB)
https://s-static.ak.facebook.com/connect/xd_arbiter.php?version=28 (21.5KiB of inline JavaScript)
http://www.dermotmurphy.com/wp-content/themes/Avada/framework/plugins/revslider/rs-plugin/js/jquery.themepunch.plugins.min.js?ver=3.7.1 (12.8KiB)
http://www.dermotmurphy.com/?callback=po_a&popoverajaxaction=popover_selective_ajax&action=popover_selective_ajax&thefrom=http%3A%2F%2Fwww.dermotmurphy.com%2F&thereferrer=&active_popover=0&_=1385404812897 (11.2KiB of inline JavaScript)
http://www.dermotmurphy.com/wp-includes/js/jquery/jquery-migrate.min.js?ver=1.2.1 (5.5KiB)