After you’ve created an account, you can favorite tracks to quickly save them for later or archive them to your own created collections. 

To favorite a track: click on the star-symbol in the track player. 

Your tracks marked as favorites can be found by clicking "Favorites", under "Your Library" on the main page.

To add a track to your collections: click on the plus-symbol in the track player. You can choose to add the track to a previously created collection or to create a new collection for which to add the track.

You can find your created collections, or create a new one, under "Your Collections" on the main page.

All your purchased tracks are automatically saved to "Purchased Tracks", which can be found under "Your Library" on the main page.