The good people at Mindful.org offer these 3 mini-mindfulness practices to get out of anxiety-induced panic mode:
There’s an excerpt of an article to go with the infographic at http://www.mindful.org/mindful-magazine/high-anxiety; the full article is in the December 2014 issue of Mindful magazine. (You can find links to subscribe to either the print or digital edition of the magazine at the end of the article.)