Please find below the steps to install & setup your demo:
1. Install & activate the theme in your Dashboard > Appearances > Themes.
2. Go to your Dashboard > Appearances > Install Plugins to install & activate all the required plugins (TLG Framework, WPBakery Page Builder, Contact Form 7).
3. Go to your Dashboard > Appearances > Install Demo.
4. Go to your Dashboard > Settings > Reading to select your homepage (as in our FAQs page, question 2: http://www.themelogi.com/tickets/topic/faq/).
5. You can also go to Appearances > Customize to change the site title, logo,…
6. To update the theme, please follow the article here: http://www.themelogi.com/knowledge/#theme_update
Also, here is some article/video you may want to have a look: