The holiday season is in full swing, and your work and social calendars are probably jam-packed for the next six weeks.

While the celebrations can be cheerful, planning and attending them can lead to exhaustion and burnout. And you might be squeezing in holiday activities while managing big work deadlines before the end of the year.

"It's such a crazy time of year," says Gloria Chan Packer, a workplace mental wellness expert and founder of Recalibrate.

Here, she shares her best tips for what you can do now to get ahead of holiday stress.

1. Start every week by reviewing your workload

It's easy to say yes to every event, meeting and project as they pile up this time of year, but that's an easy way to overextend yourself.

To rein it in, Packer recommends starting every week by reviewing your commitments, deadlines and deliverables for the next seven days. Then gauge whether you'll be able to get to it all.

If your workload doesn't feel manageable, start reprioritizing things that are more flexible. You may not be able to move a big project deadline, but a coffee catch-up with a client might be able to wait until January.

Ask your manager for guidance to determine what tasks or meetings are essential. Instead of assuming everything being asked of you is high priority, ask the requester how urgent it really is and when exactly they need something from you.

As for managing holiday party invites, Packer recommends setting a number of events you commit to each week so you have a pre-determined limit for what you say yes and no to.

2. Schedule weekly downtime now

Most of us are used to packing our work calendars with meetings, but not enough people use their calendar to set aside time to rest and recharge, Packer says.

Choose a time each week to block out a few hours of protected focus time. Maybe you block every Friday morning as a buffer time to catch up on things that didn't get your attention that week, Packer says.

Do it now before you forget or more events land on your calendar.

Don't forget to schedule in time for your own personal breaks, too. For those who have a hard time doing so, Packer recommends tying breaks into things you do every day. Try blocking off five extra minutes while you make your morning coffee to not look at your phone or computer; instead, take some deep breaths or move around and stretch.

If something comes up, it's OK to move your protected time block, Packer says. Whatever you do, don't delete it altogether.

"You can't run in the red or operate at a loss forever," she adds.

3. Prepare your 'no thank you' response

If it's hard for you to say no to things, Packer recommends preparing a simple response you can use to turn down invitations or other requests.

You can show your appreciation, she says, and above all, be concise when you express your boundary. If you're open to it, you can propose reopening the conversation at a later time when your schedule is more flexible.

Her recommended response: "Thank you for including me. I wish I could make it, but I'm already committed. I hope you all have a great time and that we can reconnect in the new year."

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