Use the nerves instead of fighting them

Before speaking, most people try to calm down. Alison Wood Brooks, a Harvard researcher, tested another approach in a 2014 study: people who told themselves "I am excited" before a speech were rated as more persuasive, confident and competent than those who told themselves "I am calm".

The racing heart and fast breathing of anxiety are close to the body's state of excitement, so relabelling them is easier than switching them off. Combine that with a few slow breaths, longer out than in, to steady your voice.