As the engineer, your key job is to select and set up the recording space, choose and position the microphone, set levels and make sure you're recording a good, clean signal at a healthy level. Like music, the louder the signal you want to record, the less audible the noise floor, but you don't want to have to speak louder than sounds natural, and you don't want to overcook things when tracking: any distortion will be very noticeable on an exposed voice part, and an otherwise great take with digital clipping won't be acceptable. If you notice clipping only when you start editing, software clip restoration tools might help to make the take usable, but it's not going to be perfect. Remember that although you may have needed to record 'hot' on analogue tape and older 16‑bit digital recording systems, modern 24‑bit A‑D converters can accommodate a much wider dynamic range, so you no longer have to track so loud: you can leave much more headroom.
I’m new to this so keep that in mind, but I use a cheap “dog training clicker” to mark my redo portions. They are very visible in the sound track. In longer recording sessions (where I won’t remember the error) I’m experimenting with using 1,2 or 3 clicks to indicate how far I plan to back up for the restart. I can often find and do the cut without have to play anything – that by having an idea of how far back I need to look.
Congratulations! You should now have a finished voiceover recording. Save a final copy with the extension _master and use this version to save another copy in the format requested by the client. But don't think your job is done when you hand everything back to your producer‑self. Running a profitable home‑based voiceover business takes more than building and equipping a home studio and recording and editing audio files. You still have to design a web site, launch a marketing campaign, and secure new clients — all of which is something we'll look at another time.
As editor, you need to turn the raw recording into the final version of the file you'll be sending to your client. Editing during a recording session can be problematic, and particularly so if you're recording in a domestic environment. How can you expect to hear the drone of the dishwasher ruining your recording if the dishwasher is still running as you edit? I'll look in more detail at setting up a voiceover recording studio next time, but for now, if recording in a separate room or isolated booth isn't an option, at least try to edit the file the following morning (or maybe at night) when there's less noise around — because hearing your recording with a fresh ear and in a quieter environment will help you to make better editing decisions, and will reveal noises that slipped your attention earlier.