It depends on the technique you’re using for the slider. I see too many scripts on your page to figure it out, but for example I see a reference to flexslider. Flexslider has an option for pausing on hover. So look at the options that the plugin you’re using has to offer.
But going another way than just use the options of the plugin will make it harder to do. Why not use the documentation of the slider?
I saw the slider you are using revolution slider has an option onHoverStop, so you should be able to set that option to true.
So look for the documentation of the slider, maybe here: https://www.themepunch.com/revslider-doc/general-settings/