Double-click on the Audacity desktop icon. It may take a few seconds for the program to fully launch.
Click "File" and select the required session. Unless you have configured it do otherwise, Audacity automatically opens a new recording session.
Click "File" when the new session opens and select "Export as WAV." This renders the collective audio tracks as one uncompressed, lossless file. Volume effects such as fades and level drops are mastering effects, meaning they apply to the mix as a whole rather than the individual elements. This is why you need to export the entire mix as a single file.
Click "File" and select "New." When prompted, name the track specifically to denote which version; for example, "Song Title Volume Fade Version."
Click "FIle" and select "Import."
Browse for the WAV file that you exported. Click on it. The file will automatically open in the new session. The audio opens as a wave-form graphic. The peaks and dips represent volume levels.
Click on the audio wave-form graphic to highlight the area to which the fade will apply. Drag the cursor right to left to highlight the specified region. For example, songs typically fade in at the beginning and fade out at the end. It's rare but not unheard of for songs to fade out and then back in.
Click "Effects" and select your desired type of fade; for example, "Fade In." This affects the appearance of the sound wave. You'll notice that the energy pattern has changed, with the sound wave peaks becoming smaller where the fade begins and gradually increasing in size as the fade gets louder. The reverse happens if you select a fade out.
Click "Save."
Hit "Play" and listen to the track to identify the best place for the recording level drop. Typically they work well just before a chorus.
Highlight a region. Aim to highlight a region that ends just before the start of a sound wave peak. The peaks represent specific sound, rather than ambient noise.
Click "Tools" and select "Trim." This brings up a scissors icon. Use the scissors to "snip" the selected region and move it.