choose simple, good rituals which are easy to do, which actually improve your surroundings, and which allow you time to collect your thoughts--this helps break the grip of panic when we're afraid we're going to pull and we have that huge list of things we think we ought be to be doing
(At first this still seem unnatural and awkward and silly, if you even remember to do it to begin with, but it gets more natural, and you get to worry just a little bit less about where your hands are and whether other folks can tell that you started to do something "bad.")