There’s many different approaches, and everyone has their preferred workflow, so I can only tell you how I would approach it (and why). You can then try it this way, then take from it what is useful for you.
I’m assuming that the “songs” are pre-recoded and don’t require any additional processing or “mastering” other than perhaps volume adjustment so that they all play with about the same “loudness” (how “loud” the music sounds may be very different to its “peak level”, so don’t expect the meters to tell you how “loud” the track is - you need to listen to the tracks).
I would deal with the music tracks first. This is a bit laborious, but it’s easy. When this is done we can move onto the fun bit
- Import all of the music tracks (easiest if you have them all in one folder so you can import them all together). They will appear in Audacity as separate tracks, one above the other.
- Use the track “Solo” buttons to listen to one track at a time and find the quietest track. Move this track to the top (either drag the track by it’s “track control panel” or use the command in the track control panel menu: http://manual.audacityteam.org/man/audio_tracks.html#Track_Control_Panel).
- Then go through each track and, using the track “Gain” slider, adjust the level so that every track sounds right against the quiet track. (we have to go quieter rather than louder, otherwise we are likely to make some tracks distorted).
- Optional: If some of the tracks are too long, you may want to trim them down at this stage, but if you’re not sure how much of each track you need, be generous and retain a bit extra - you can trim it down later.
- When all of the tracks sound right, export them to a new folder in WAV format using “Export Multiple” (http://manual.audacityteam.org/man/export_multiple.html). Always use WAV during the production stage - if you need MP3 for the final show, convert as the final step, but keep a WAV format backup copy.
Your music files are now ready to drop into the show, and save for a bit of trimming they are now “drop and go” ready.
Check that the files have exported OK, and then close the project so we start the next part with a fresh project.
Now start to build up the show by importing the commentary and the processed files.
Group similar audio clips together on the same track. For example, if there are two voices, use a separate track for each voice. If one voice was recorded in two different sessions, then you may need to tweak one session differently from the other session, so give each its own track.
Because the volume for all of the music tracks are matched, we can group those one one track.
Use the Time Shift tool to move each audio clip into the right place on an appropriate track (I generally move them “roughly” to the right place first, then go through and precisely adjust them to get a nice flow.)
Each Audacity track should now, individually, sound OK, but some tracks may be louder, quieter, have more/less bass, more/less treble … than other tracks. So now you can process the tracks with Equalization, compression, and whatever else you need, one track at a time, so that the you end up with a show that “gels” as a homogeneous whole.
Back-up, back-up, back-up… Don’t forget to make regular back-ups, and don’t overwrite your back-ups. Give each back-up a unique name so that you have a trail of backups going back to when you started the project. Back-ups are a worthless waste of time, until you need one
When you have “finished” the show (and made a back-up), export the show in WAV format, then take a good long break and give your ears a rest.
When you come back to it, listen critically to your exported WAV file, preferably on several different systems with different speakers / headphones. What did you do wrong? Can you live with it or do you need to go back and fix something? If it’s about right, go back into the project and export a new copy in whatever format you need.