Originally Posted by Hummingbird
... Most recording software also have automation settings where you can change volumes on a track as you go through it.


This is commonly called "riding the waves" or "riding the faders" where you adjust the volume of individual tracks during the send-to-tape process (be it automation or an actual engineer's hands). This is not really the best way, IMHO and based on books I've read. It's better to use slight compression. Slight, because you want the nuances of your voice to shine through. But I definitely recommend some compression. You can adjust the ratio settings, I don't use anything harder than "4:1" on vocals.

Back in the old days, when people still used tape, you could do an initial recording and "mix down" - for example record 12 drum tracks (one for each drum/cymbal) and then "mix down" the drums to only 2 or 4 tracks. Eventually everything got mixed down to a single pair of stereo tracks. During the mix-down process, the engineer would "ride the waves" and make manual adjustments in volume. These days, this method is slightly antiquated. You can use automation but it's not the same and nearly impossible if you have multiple vocal tracks (harmonies) to mix-down.