Thank for the great question. You can download the SoundTouch app on the computer that has your music. You can download it by visiting here: http://bose.life/2hE9hMe. Please note the music library must be managed by either iTunes or Windows Media player.
Once you have the SoundTouch app installed on your computer, please open the app and click on "Add service" on the left side. Then, click on Music Library on Computer. This will guide you through the entire process of uploading your playlist and streaming on your SoundTouch system.
Hope this helps and gets you started in the right direction. Should you need any further assistance, please feel free to reach out to our Bose Support line by navigating to this page here for contact info: http://bose.life/2qwENj4.
Very best regards,