One of the main reasons people feel so stressed out is that with the invention of the Internet, email and, most notably, the smartphone, it often feels like you are attached to work, you can never fully disconnect and be released from your work duties. The pressure to always be connected is hard to let go of, especially when your smartphone is in your hand.
One way to combat this is to set guidelines for yourself on when you will and will not answer an email or message. Turn the phone off when you are home and off of work, if that is not possible, schedule when you will check your messages so it can be planned and contained instead of all consuming. When you are not at work, make sure you can keep those boundaries firm and not be drawn to work 24/7.
While in the office there are many ways you can destress yourself. The easiest one is to take deep breaths. If you are in a tense moment, stop what you are doing, close your eyes and take a deep breath and then another and another until you feel your body calm down. Take a minute to center yourself. Once you are more grounded, you can act instead of react and handle the situation more calmly. Breathing is so important and it is free, easy and you can do it anywhere you are.
When on lunch or a break try to get outside and take a walk. The fresh air and nature are beneficial in many ways. The sun will help your body produce vitamin D which is essential for good moods and emotional wellbeing. Being outside in nature has a calming effect, as well as just the physical exertion of taking a walk.
If you like tea, drinking a warm cup of tea can be relaxing, especially an herbal tea with chamomile or mint. Eating well can also be key in having a life with less stress. Nourish your body inside and out. If you are feeding it well, it will treat you well. Sugar and highly-processed foods can cause spikes and big drops in blood sugar which can acutely affect your mood and exacerbate any stress you may be feeling. Eating whole foods (as opposed to white flour products) and carbohydrates that are lower on the glycemic index can help stabilize your blood sugar and prevent the shifts that can cause mood swings.
Lastly, find a support system, whether it is inside or outside of the company you are in, to help you when you need it. People who you can use as a sounding board with your concerns and can help you strategically work to find solutions in the workplace to have a happier and more productive office environment. Having people around you who help build you up and help you achieve your goals are the people you want around you. Distance from those who will try to bring you down or cause unnecessary stress.