If you work alone in a room (or are willing to use headphones) you can lighten up your design work with some nice music in the background. I have made a complete u-turn on this, starting off with requiring library-like silence to concentrate.
Not all music is suitable for work. Dominant lyrics, or tunes that stick in your head do not work. Music that is so slow that it puts you to sleep is also not ideal. Audio advertising make your office feel like a car repair shop. And the worst of all, repetition is annoying (“hey here is that same sone again for the fifth time”).
The repetition argument pretty much kills the traditional CD option, and even your personal iTunes library will be exhausted soon. Most of all, your personal music purchases of the past are unlikely to be suited for work music.
Internet streaming apps are the solution. Spotify is great, but it requires you to find the right (long) playlist that fits your work requirements. And that is difficult. Pandora is another solution. The genre or artist radio stations are good, but also here you run out of new music. After playing the cool jazz radio station for 2 days you start recognizing the songs.
So, the app I love is Songza. It has far less choice in terms of songs, but it has a treasure of playlists for any occasion you can think of, including work: acoustic, jazz, electronic. Unlike Pandora, the songs are curated by human experts rather than automatic algorithms.
Note that these services will not work in all countries around the world (unfortunately).
Which music services do you use?