Recording my screen and voice

I actually record then talk over the recording later. it works well.

You can set up Quicktime Player to record your screen. Instructions for this are online and easy to follow and accessible using VoiceOver. You may need to set up a hotspot to stop recording.
Audio will come out of your speakers and your Mac's mic will pick up your voice. I recently used this technique to show the accessibility of a client's website. It works well, even though the audio isn't studio-quality.

I was really struggling with this and found this post so thought I'd update with my findings.

Firstly, I was going into Quick time and starting a new screen recording. This brings up the same dialog as Cmd+Shift+5. So I setup my microphone, choose to record entire screen and hit record and then....

Well, at that point it's not clear what is happening. QuickTime Player has no windows. There is a system dialog you can find using Application Chooser (VO+F1 twice I think) but it's just the same record window again.

I am certain that when I last tried this, at this point QUicktime would have some sort of page up with some controls, most importantly stop recording. However, now this does not appear to be the case.

However, I found that if I then press Cmd_Shift+5 again the dialog now has the option to Stop Recording. If you select that, you go to a weird dialog that has just one button called, I think, Markup. This dialog is weird because whatever button you press it goes ping until you activate the Markup button with VO+Space. Then you get a menu where you can choose Done or Delete.

If you choose Done it saves it to wherever you selected under Options before. So when I tried this I had a new file called "Screen Recording" with a timestamp after it and it was in my Desktop.

I'm not sure if this change was intentional or if it's a VoiceOver bug. But it's not very intuitive. Unless you know the Cmd+Shift+5 shortcut then I'm not sure how you would have any idea what to do. I certainly didn't!

(Edit - I added this to the wrong forum post, although this one was quite similar. I'll leave it here as I'm not sure how to delete it and it's still relevant, but apologies as I'll post the exact same thing again in the right place...)

What I'd really like to do is record an audio file using a DAW (like Garageband) and have my voice as one channel and the system output as another channel. But the MacOS audio output can't be configured as an audio input channel.

If you have two microphones, you can use one for voice, then set the second microphone directly in front of the speaker. There will be some cross channel bleed, but it produces much better quality than you get from QuickTime Player.

I have a dual-channel Scarlett analog to digital box with dual microphone support. But, last year, in a fit of stupidity, I sold my second microphone. Crap. That leaves me with one microphone for my voice, and I'll run that through the Scarlett.

As luck would have it, my Logitech webcam has a microphone. And MacOS comes with the MIDI Setup tool, which will let me configure my webcam mic and Scarlett mic as a single audio input device. Assuming I can get this to work again, I'll stick the webcam in front of the speaker, and I should be good.

Hey. If anyone has a better idea, let me know.

A similar question was asked here last week, and I posted a rather long reply with instructions on how to do something like this without having to record your Mac using a microphone. Using Blackhole as I mentioned in my reply to that thread, the microphone feed comes through a different set of channels so you can strip and split the audio later during compression using ffmpeg. I'm willing to provide assistance with my setup if necessary, just reply either there on here as I will be subscribing to this thread as well.