It's important and helpful to stop whatever you are doing or pause when you are feeling worried or anxious about something for no reason.
In a sitting position, take a deep breath: close your eyes, breathe from you nose and slowly exhale through your mouth. Do the inhale-exhale exercises until you feel your body has relaxed.
Then, when you are calm and collected, tell yourself to be calm and peaceful, and that you got this. Expect yourself to be kind to yourself by giving your body a rest. Drink warm water, one glass at a time, and stay calm when you feel overwhelmed and worried that an anxiety-visit is coming on.
Make it your regular habit to sit, walk, run, exercise out in the sun everyday for an hour or two. Sunlight plays a significant role in improving serotonin levels to full strength capacity in combating psychological attacks of anxiety and stress.
Supplement with Magnesium, Zinc and Vitamin C Sodium Ascorbate. Make sure you get them from trusted supplier. I recommend iHerb.