Download and install the latest version of a digital media player software such as iTunes online for free, if you do not already have it.
Purchase new music to add to your music library. Download it from a digital music store, such as the iTunes music store, Amazon.com, or from another online music store. Alternatively, purchase CDs and import them into your music library.
Create a new playlist for your party on your digital music player. Select the music that you would like to play from the music library on your digital music player. Compile a large enough list to keep music playing for the duration of your party. Check if your digital music player will note how many hours of music are on your playlist.
Set up speakers to optimize the music experience for your party guests. Use a modest speaker sound system that can easily be plugged in and connected to your computer to ensure that your guests can all hear and enjoy your musical selections.
Keep your computer or laptop in a discreet location at the party. Double-check that you have selected enough hours of music for your playlist or set it to repeat once it reaches the end of the playlist. Choose to turn your selections on shuffle or not. Periodically check your computer throughout the party to see if you must drag in or remove tracks at the last minute from your party playlist.