Pick the right microphone - Dynamic mics like the Sure SM7B are great for narration and vocals, as they minimize noise, but they also "color" the sound. For foley or more true voice sound, compressor microphones are better.
Note Phantom power - turn on phantom power only if using compressor microphones. Dynamic mics often do not require phantom power.
Check Audio Signal Flow - Check mic connection, interface power and levels, cloud lifter, USB to computer and Software. Before you can record you need a strong reliable signal.
Check Audition and input/output Settings - Check that Scarlett Interface is connected and that Focusrite software is installed. Check I/O settings. There should be 4 input tracks. For playback, make sure buffer is high enough so there is not distortion.
Check for clipping and plosives - Record a segment of the audio sources at volume and check that audio does not clip or distort. If so, reduce recording gain.
Minimize noise and audio bleed - listen for any sounds that might disrupt your session and isolate. Record a bit of ambient to assess noise levels.
Waveforms - as you continue the recording session, always be mindful of the waveforms and that the software is actually recording and that you are not recording over something you already recorded. You do not want to lose a great take.
Communicate - Agree on hand signals to let your narrator know when they can begin and when they need to pause, or whether they need to be louder or quieter. If you have access to talk back, use that. Allow a narrator to finish their sentence before interrupting.
Pausing and Saving - Every five minutes of recording, pause the session, let your narrator know to take a pause and save your file. This is good practice.
Finally, have Fun!
Mic Position - Make sure the microphone diaphragm faces the source directly. In the case of narration the position slightly affects the EQ. For voice, angle the mic toward the mouth.
Mic Distance - This will depend on the vocal quality of the narrator. Start about six inches away from mic and record a section. Being closer to the mic increases the low frequencies, but might cause plosive pops. Moving away from the mic will reduce lows and some mids but might make the audio seem thin
Scripts and papers - if you have access to music stands use them to read your script. Do not fiddle with the pages as you are recording. Always fit the entire sentence or section in one page so you are not turning the page to finish a sentence or section.
Test voice Dynamics - At the start of the session, record a section that features the quietest and loudest parts of your script. This will help the engineer figure out the levels.
Check for plosives and Sibilants - Say words with Ps, Ts and Ss. Check that the audio does not clip or pop. You might need to use a pop filter. Say a phrase like "Singing to Take Place Shortly. Take Some Pictures!"
Mistakes - Narration mistakes happen. IT'S OK! The engineer will continue to record. Pause, breathe and start again from the beginning of the last sentence and continue.
Different Voice - If you have a chance to hear your voice back, it will sound weird. Always does. The voice inside our heads is not the same as how other hear it. That is ok.
Finally, have Fun!