Go to [Bonus Materials]. Highlight [Music Videos], push the [Left arrow to highlight the number "420", push [Enter].
On the second [Bonus Material] page, scroll [Down] to highlight [Universal Showcase]. Push the [Right arrow to highlight the number "420", push [Enter].
On the last page of the [Bonus Material], scroll [Down] to the bottom of the page to highlight the back arrow. Push [Up] to highlight the number "420".
Also on the last page of the [Bonus Material], scroll [Down] to highlight [DVD Newsletter]. Push the [Right arrow to highlight the number "420".
In [Bonus Materials], on the first page, go [Down] to "Hide the Stash". Press the [Right arrow button and you will see a red lighter. Press [Enter] to access the egg.