Connect the computer to the turntable with a USB cable if your turntable has a USB port. Follow the manufacturer's instructions for installing specific software to use the turntable with the computer.
Connect the computer to the stereo amplifier. Connect the stereo jacks into the amplifier and the phono plug into the "Line In" of your computer's sound card if the turntable is not USB-enabled.
Install sound-editing software of your choice, such as Mixcraft or Spin it Again (See Resources). Follow the manufacturer's instructions throughout installation.
Test that you correctly connected the equipment. Turn on the computer, the turntable and the amplifier. Start the sound-editing software and play a vinyl disc to see whether the PC receives the signals from the turntable and whether you can hear the song through the PC's speakers.
Mute every other recording track on your computer and only allow recording from the turntable and the amplifier. Open the volume control on your PC and set the "Line-In" volume.
Start a new project in your sound-editing software. Create a track that is long enough to record the entire side of a vinyl. Set the sound quality to 44100 Hz and to stereo recording.
Start the recording on the PC. Record 10 seconds of silence, then start the vinyl recording. Play the recording until the end. Stop the recording on the PC. Repeat the same steps to transfer the other side of the vinyl.