Go to the course menu Activities > Assignments or find link within the course content:
Click Record Audio.
The next process shows recording audio, but video is the same.
Click New Recording.
Make your recording and click Stop Recording when you are finished.
Content goes here
Preview your audio to ensure it sounds correct, then click Add.
Provide a Title and a Description for your audio file, then click Add.
Add any additional files or comments, then click Submit.
Click Done.