Keeping visitors on your page - how to make them faster
There's lots of sites to help you find out where the bottlenecks are, like:
Website speed test
https://gtmetrix.com/
There's at least 11 ways you can speed it up that are shown at:
11 Ways to Accelerate Page Load Time Before Your Prospects Bounce
I especially like the 'limit the number of WP plugins' comment as well.
Remember - people have short attention spans - get them their info FAST so you can increase your conversions today.
Enjoy!