Use distilled water instead of tap water. Tap water has minerals that can damage the polish on your AirPods.
If you use your AirPods at night a lot, keep their case right next to your bed. If you like to use your AirPods on the go, carry their case with you in your bag. Just make sure it’s closed so dirt and dust particles don’t get inside.
If someone asks to borrow your AirPods, kindly tell them you paid a lot of money for them. Offer to let them borrow a cheaper pair of regular headphones instead.