I usually try to do deep breathing, but when I’m surrounded by people it makes it worse and can lead to an anxiety attack. I have one friend that also has anxiety and she’s really good at calming me down. Another problem for me is I have minor OCD, so if someone starts moving my stuff it makes me really anxious. All I can recommend is finding a friend that can calm you down, making sure you don’t go into too crowded areas, and deep breathing.