Putting on an oxygen mask is one of my favorite metaphors. I use it all the time. It’s based on that announcement that flight attendants make before the flight takes off: “If you’re traveling with children or people in need of help, make sure your own oxygen mask is secure before assisting others.” In other words, take care of yourself if you’re hoping to be of any help to anybody else.

I didn’t come up with this metaphor. Self-help groups have been using it for years. But recently it’s become an excellent reminder for myself.

For instance, the other week I had agreed to go to a great dinner party with a couple of famous people whose work I admire. I’d hired the babysitter. She had arrived, and I was checking my cell phone to make sure I knew where to go. I was dressed.

And I realized that I was exhausted. I had just gotten home from traveling. I wanted to be in my pajamas. I wanted an easy dinner (cold cereal) with my daughter, give her a bath, and read bedtime books with her. I didn’t want to have to exert the energy to make conversation — even scintillating conversation where I probably would have said very little.

So I called the person putting on the party and apologized, telling her I wouldn’t make it. I wrote the babysitter a check and sent her home. Oxygen mask.

I’m also trying to use the oxygen mask strategy with larger life events. It’s a way of prioritizing. It can be so easy for me to put other things and people first: my friends, my job, my grocery shopping, my plans for the future. I can schedule days and weeks so that I have very little down time.

As a college professor, I’m in a career where this isn’t all that usual. My colleagues and I often sign up for multiple committees, advise multiple independent studies and internships, and take on various leadership roles because that’s what we should do. We want to be of service. We want to make our campus better.

I also have friends who take seriously their roles in their communities, volunteering to teach Sunday School, guiding neighborhood organizations, coaching youth sports, helping put on school fundraisers.

This service is valid and valuable. These are the efforts of people who care about their communities. I’m not in any way trying to suggest that dedicated, hopeful, generous people should step down. That’s not what this column is about.

Instead what I’m interested in is me. I offer the oxygen mask metaphor to folks I love all the time, encouraging them to let themselves off the hook. I tell them that they’re worth taking care of, and that they can let themselves off the hook (as author Anne Lamott says). But I’m not always good at taking my own advice. When I made the phone call apologizing for not attending the dinner party, I felt a little stab in my stomach. A part of my body told me, “No! No! You can’t do this! If you make a little effort, you can go to this party. The babysitter is already here!” Old habits, old patterns were nudging me along. “Come on,” they said. “You’ll be letting people down. You don’t want to be that kind of person. Suck it up. Head out the door.”

For whatever reason, I was able to treat myself as I’d treat a friend. I realized that if my friend had declined a party invitation at the last minute because of exhaustion, I’d congratulate her. I’d be impressed. So I thought I’d give it a try.

And after I hung up the phone and sent the babysitter back to her home, my body relaxed in ways I could immediately feel.

I’m trying to remind myself of this. Perhaps it’s a kind of opportunity for 2014. I’ve had several years now that have been challenging in a variety of ways, and it’s not a bad idea for me to remember that I won’t be good to the people closest to me and the larger world around me if I run out of oxygen and pass out on the airplane.