Connect the record player to your computer by plugging the RCA end of the cable into the output on your record player and the 1/8-inch end into your line-in input on your computer.
Donwload and install the latest version of Audacity.
Launch Audacity and create a new project by clicking "File" then "New."
Change the recording input to "Line-in" from the drop-down menu next to the volume faders. Turn the volume for the microphone input all the way up by sliding the fader over with your mouse.
Click on the "Record" button to begin recording in Audacity, then start playing the vinyl on your record player. Audacity records the music being played from the vinyl. After the song has finished playing, press the "Stop" button. Go to the "File" menu and select "Export to MP3." Give the file a name and save it to your desktop. Repeat these steps for each track on the vinyl.
Connect the record player to your computer by plugging the RCA end of the cable into the output on your record player and the 1/8-inch end into your line-in input on your computer.
Launch GarageBand and click on "New Music Project." Leave meter and tempo settings on default. Click "Create."
Click on the "Track" menu and select "New Track..." Then click on "Real Instrument" and then "Create."
Click on the "Record" button to begin recording in GarageBand, then play the vinyl on your record player. Garage Band records the music being played from the vinyl. After the song has finished playing, press the "Stop" button. Go to the "File" menu and select "Save As..." By default, GarageBand saves your project as an AAC file. Go ahead and save it as an AAC.
Drag the AAC file into your iTunes library. Right click on the file and select "Convert to MP3."