Verbally Pumping Up

Just as the boxer, wrestler, and karate champion have to do a standard workout before they get into the arena to defend themselves against their opponents, you have to do the same.
They have a daily physical exercise regimen that requires exercises to stretch and build up the muscles in their upper and lower body. They do this every day to make themselves stronger, more limber, and more confident in their physical abilities.
Similarly, you need to have a daily verbal exercise regimen that prepares you for any verbally venomous opponent you will encounter. You need to work out the physical, verbal, and communication skills. Doing exercises for posture, breathing, voice, jaw, nasality, pronunciation, and communication skills will help you become more verbally limber and more confident in your communication abilities.