The holidays are typically a time for celebration and mirth, but for many people, they're also incredibly stressful. And if your level of anxiety is rising this December, you're not alone.

Nearly half, 41% of U.S. adults say their stress increases this time of year, according to the American Psychological Association. "I think there's solace to be had in that you're not alone in feeling super stressed," says happiness expert Jessica Weiss.

Weiss has spent more than a decade giving talks and doing workshops about happiness at work, including a TED talk entitled "Happiness: It's an Inside Job." Here are her tips for how to improve your mood this season.

1. Maintain social connections

For Weiss, when you're feeling stressed out, "the most important thing is maintaining social connections," she says. Specifically, try to "have some micro moments of connection."  

These can be with family and friends and don't have to be too long. "I'm talking like 10 minutes," she says. Ideally they happen in person, but if they have to be via phone call or text, that's fine, too. Try to have at least two moments of connection per day.

"Even brief moments of a positive interaction will boost happiness and reduce stress," she says.

2. Maintain your routine

Second, whatever the holiday season brings in terms of an array of seasonal activities, "maintain your regular routines," she says.

For Weiss, it's exercise, but "maybe your regular routine is reading for a half an hour in the morning," she says. "Maybe your regular routine is doing breath work before you start your day. Maybe your regular routine is unwinding with a hot bath."

It's especially important to keep doing whatever it is you do to destress. That "will make everything feel much more normal," she says.

3. Say 'no' when you need to

Finally, it is very easy for schedules to fill up this time of year, but you don't have to say yes to every invitation. "Say no to anything that drains you," says Weiss.

"There are going to be certain things that are essential, right?" she says, maybe family gatherings, for example. But, she adds, "the nonessential things are the things that you can say no to, and the litmus test is, what's the worst thing that can happen if I say 'no' to those?"

If you realize there won't be major repercussions, that's your opportunity to say no and get that time back.

Ultimately, Weiss believes that "sometimes less celebration means more joy."

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