Connect a cable to each of the stereo output jacks on your audio interface. The type of cable required varies depending on what model of audio interface you have, but it is typically a 1/4-inch cable or, less often, a phono speaker cable. Connect each cable to the relevant speaker, for example the left cable to the left speaker if using powered speakers. If you are using non-powered speakers connected to an amplifier, connect the cables to the amplifier.
Double-click the desktop icon of your preferred music production software program, for example Cubase, Mixcraft or Audacity.
Click "File" and select "Open Recent." Click on the session for which you want to create a stereo mix.
Rename all paired tracks. For example, if you recorded two takes of the same guitar part or two versions of the lead vocal, click on the channel strip for the audio in question to edit it. Name one of the audio tracks "Guitar right" and the other track "Guitar left." Do this for any pair of audio tracks.
Click on "Guitar left" and turn the "Pan" dial hard left. This sends this track to the left of the stereo channel only. Pan the other guitar hard right. Repeat the process for all paired tracks, so they are split left and right.
Pan the remaining tracks to your preference. Panning creates space in the stereo mix. While you should be guided by what sounds good, it's typically preferable to leave low frequency instruments such as bass and kick drums in the center. Pan everything else slightly off center.
Click "File" and select "New Audio Track." When prompted, select "Stereo." Name the track "Stereo Mix Down."
Click on "Stereo Mix Down" and under "Inputs" select "Stereo Bus."
Click "Send To" on the "Master Output" channel strip and select "Stereo Mix Down." This splits the master mix into a stereo channel. The panning and mixing information that you added previously will be carried over into the new channel.
Click on "Stereo Mix Down" and select "Export As Wav." Name the new file "Song name Stereo Mix."