Use One Bud at a Time
My favorite AirPod trick is to use on AirPod at a time. I do this for a few reasons.
The first reason is so that I can listen to an audiobook or podcast while still being aware of what is around me. This is great for walking around outside or for working on housework with someone else at home who may need me to hear when they ask for help with something.
The next reason is to expand battery life when I am on phone calls. With one AirPod in I can easily switch to the second AirPod when the battery life on the first one dies. As long as the microphone settings are turned to Automatic the AirPods will use the microphone on whichever one is in your ear.
This is also allows you to share a bud with someone to watch a video together or to listen to music at the same time.