How do I defer parsing JavaScript?

Hi,

I’ve looked around, found a few articles, but nothing really to help a relative amateur like myself when it comes to messing about with Java.

I’m trying to optimize my website so that it runs as smoothly as possible.

When I run Page Speed on GTMetrix, I get a poor score of F in the “Defer Parsing of JavaScript” section. I look at the details and this is what is says.

https://gtmetrix.com/reports/www.buildyourownhouse.uk.com/QsRpIktC

489.1KiB of JavaScript is parsed during initial page load. Defer parsing JavaScript to reduce blocking of page rendering.

https://www.buildyourownhouse.uk.com/wp-content/plugins/form-maker/js/jquery-ui.js?ver=3.8.1 (255.6KiB)
https://www.buildyourownhouse.uk.com/wp-includes/js/jquery/jquery.js?ver=1.10.2 (83.7KiB)
https://www.buildyourownhouse.uk.com/wp-content/plugins/form-maker/js/main_front_end.js?ver=3.8.1 (41.6KiB)
https://www.buildyourownhouse.uk.com/wp-content/plugins/form-maker/js/calendar.js?ver=3.8.1 (31.7KiB)
https://static.ak.facebook.com/connect/xd_arbiter.php?version=40 (21.3KiB of inline JavaScript)
https://s-static.ak.facebook.com/connect/xd_arbiter.php?version=40 (21.3KiB of inline JavaScript)
https://www.buildyourownhouse.uk.com/wp-content/plugins/form-maker/js/jquery.ui.slider.js?ver=3.8.1 (10.8KiB)
https://www.buildyourownhouse.uk.com/wp-content/plugins/form-maker/js/calendar_function.js?ver=3.8.1 (8.3KiB)
https://www.buildyourownhouse.uk.com/wp-includes/js/jquery/jquery-migrate.min.js?ver=1.2.1 (5.5KiB)
https://www.buildyourownhouse.uk.com/wp-content/plugins/form-maker/js/if_gmap_front_end.js?ver=3.8.1 (3.5KiB)
https://www.buildyourownhouse.uk.com/wp-content/plugins/form-maker/js/calendar-setup.js?ver=3.8.1 (3.4KiB)
https://maps.google.com/maps/api/js?sensor=false&ver=3.8.1 (1.5KiB)
https://www.buildyourownhouse.uk.com/ (734B of inline JavaScript)

Most of the problems seem to come from one plugin, the web durado form maker. This is not on the home page, but on an entirely different page. The form is an essential part of the website.

Does anyone know how and what I should do so that I get a better score on my Page Speed for “Defer parsing of JavaScript”?

What files would I need to edit?

My web address is https://www.buildyourownhouse.uk.com

Any help would be hugely appreciated.

Anthony