Happiness expert Gretchen Rubin shares tips to avoid stress over the holidays

Travel, parties and family obligations can make the holiday season a stressful time for many people. The key to maintaining your sanity during the holidays is avoiding falling into "empty," according to happiness expert and New York Times best-selling author Gretchen Rubin. 

"Don't let yourself fall into empty… keep cash in your wallet, keep gas in your car, keep snacks in the bag, keep your phone charged," Rubin told "CBS This Morning" on Monday. "Get organized before you go so that it's easier when you come back."

Rubin said people often try to "eke out" the most from their vacation, but she recommended giving yourself a buffer of time before you have to return to your normal day-to-day life. 

"So you come back Sunday night and then everything starts on Monday. If you can, give yourself a little buffer. Read your holiday book, unpack, and have a little holiday relaxation," she said.

To keep small children occupied while on the road — without relying on screens — Rubin suggests packing a "fun bag."

"Give them a little backpack with all the little things that you get in gift bags over the years: the little figurines, the little travel games. Stick it in there, never let them play with the stuff unless they're actually traveling," she said.

In the throes of the holiday season, Rubin recommends that parents alternate responsibilities and pace themselves. Each parent should give their partner a break, she said, so that no one burns out. 

If it all becomes too much and you want to say no to an invitation from friends or relatives, "don't over-explain," Rubin said. "Just say: 'That doesn't work for us.'."

No need to give a detailed rationale, she said, but you can offer an alternative option to connect with loved ones. 

"Just stay focused on what you're there for, which is relationships," she said. "... We're here to have fun together."