Choose the software you want to use. It's best to use a program that allows you to slow down music without changing the pitch. Renegade Minds and Amazing Slow Downer are two choices. Audacity, available for PC and Mac, is a free option. More expensive audio recording software such as Pro Tools will also work. There are several choice available. (See Resources.)
Burn songs you want to slow down and learn onto your computer. You can use Windows Media Player to burn tracks from your CDs to your computer hard drive, or Burn OS X if you have a Mac. Both programs are free and easy to use. Insert the CD with the tracks you want to burn, go to the "Burn" menu and select the tracks on the disc you want to transfer to your computer.
Open your audio software and on the "File" menu select the "Open" option. Browse to the location on your computer where the music track you want to open is located. Click the file to open it. The song file will open for editing in your software. For Audacity, all you need to do to adjust the speed of the song is use the slider bar on the toolbar to raise or lower the speed. Half-speed is a good place to start for learning fast passages. Amazing Slower Downer also works with a slider bar. Both programs have loop options to allow you to play a slowed passage repeatedly until you learn it.