Step by step method to view

YouTube Material Design?

1.Open developer tool if you are using Google chrome.  

2. Goto Resourse --> Cookies --->www.youtube.com---> delete VISITOR.

3.Click on console and enter this

document.cookie="VISITOR_INFO1_LIVE=Qa1hUZu3gtk;path=/;domain=.youtube.com";

4.Press Enter and reload YouTube.