Open Adobe Audition. Once it loads, open the default multitrack view by clicking the "Multitrack" button in the toolbar.
Open the "File" menu and choose "Open Project." A file selection dialogue will appear. Navigate to the project you want to master and double-click it. Audition will load and display the project in multitrack format.
Click on the track header of any displayed track. Open the "Edit" menu and choose "Select All." All of the tracks in your project will be highlighted.
Right-click any track. A contextual menu will appear. Select "Master Output" from the "Mixdown" sub-menu. Audition will combine all the tracks in your project into a single file for mastering.
Open the "Effects" menu and select "Mastering Rack." The default mastering screen will appear.
Click on the disclosure triangle next to the first empty field beneath "FX" in the mastering screen. A pop-up menu listing available mixing and mastering devices will appear. Choose "Parametric Equalizer" from the "Filter and EQ" sub-menu. A basic equalizer interface will be displayed. Click the "Loop" and "Play" buttons to begin playback of your track.
Adjust the equalization of your recording as needed. Most equalization should generally take place during the mixing stage on a track-by-track basis. At the mastering stage, EQ is primarily used to make the track better accommodate the medium for which it is intended. For example, if you are mastering audio to post on the Internet, boosting bass frequencies will help the bass stand out when playing through small computer speakers.
Click on the disclosure triangle beside the next empty field beneath "FX" in the mastering window. Choose "Multiband Compressor" from the pop-up menu. The compressor interface will appear.
Choose an appropriate preset from the pop-up menu at the top of the compressor interface. For example, if you are mastering a music track for burning to a CD, choose "CD" from the "Music" sub-menu. Audition's compressor includes several dozen mastering presets covering every common mastering approach.
Listen to the track all the way through without making further adjustments. If you are satisfied with the result, click the "OK" button at the bottom of the mastering interface. Audition will create a new file containing your track with all established mastering parameters applied.
Open the "File" menu and choose "Save As." The file dialogue will appear. Name your track and choose an audio format from the drop-down menu. Make sure to choose a format appropriate to the track's destination medium. For example, choose "16-bit WAV" if it will be burned to a compact disc. Consult Audition's documentation for details on the different formats and their appropriate contexts.