To add a video to your Favorites, you can do so from either the application or the website.
The application: Once you've chosen your video, press the "Favorite" icon, which will become active. Your video is now a Favorite.
To find your videos in Favorites, simply go to the "Browse" menu and click on the "Favorites" logo in the top right-hand corner.
Then enter the "Favorites" menu, where you'll find all your favorite videos.
The website: Just as in the application, once you've chosen your video, simply click on the "Favourite" icon, which will become active. Your video is now a Favourite.
You'll find the "Favorites" menu in your Profile. Click on "See all" to display all your favorite videos.