This is an exercise the guides taught me for centering myself. It's really helpful when I'm going to be in a social situation and I'm feeling nervous.
Stand up straight with your feet slightly apart. Clasp your hands infront of you, one about the other, with the fingers of each hand curled up inside the fingers of the other. Your hands should look a bit like a yin-yang. Hold your clasped hands level with your belly chakra, and take a few slow, deep breaths, in through your nose and out through your mouth. You should feel better immediately.
