how can i make or install a WP demo viewer?

i would like to be able to show clients different layout options of a live theme demo before actually installing it..

i would really like to be able to make a demo page for my customers and eventual themes i design like a page like this example: https://www.web2feel.com/ or on the wordpress themes pages where you can click on view demo or download.

my website is lizartlizard.com