First Go to site https://www.tawk.to/. Create a free account. Create a new site. After create a new site, tawk.to will send you a mail with magic script. Use this magic script in plugin configuration later.
Download KheyaNopLiveChat and copy the same version into the site Plugins folder.
From Site Admin panel go to Configuration > Plugins > Local Plugins and search for KheyaNopLiveChat. If not found reload the list of plugins. Then install the plugin and Enable it from Edit option.
Click on Configuration button and copy the magic script from mail to textbox and save it. Congratulations almost done.
Finally clear cache from Admin panel and restart application and browse the site. You can see chat window on your screen at right side.
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