I usually load up a thumbdrive with MP3s of songs I want to learn. In the "old" days I would make a mix-tape or mix-cd. Then I'll sing along to that when driving to my gig. If it's been a long drive, I can usually play one or two of the songs at that gig.

But I also love Youtube and Spotify. I put my laptop on my piano, and just play and sing along to the music. Great fun! And I love to have almost every thinkable version of a song ready for listening.

DocZ