The first way to share your music is to link your artist page on your various social networks. As people go to discover your music, you will be able to get paid when they listen and check you out (even if it is less than a penny, these things do add up). This will also make it so that your new fans can go to a place where they can add your music and get locked in to a lasting relationship with your music, if they star your music. You can get this URL by clicking the share button located on your artist page (note: you need to have uploaded your music to Spotify first) and copying the URL in the tweet you would send out. You can put this URL as a link with the Spotify logo on your website or anywhere else you would like to promote your music.
If you have already signed up for Spotify and linked your Facebook account to it, you will notice that all of your friends who are already on Spotify appear on a list. All of your friends on this list can have tracks, or playlists dragged on to their name and they will appear in their inbox. While sending only your own track can be spammy, but sending a relevant playlist can be an awesome way to promote yourself and other artists.
This is the only beginning and we look forward to finding more awesome way to promote your music on Spotify.