Some people are super comfortable on camera, and others not so much. Even for seasoned veterans, preparation is key. Rehearsing the script or interview questions in front of a mirror beforehand lets you see in real time some habits you may have that you’re not aware of. Some people hate watching themselves in a mirror or even on video, but it’s so much better to watch yourself before anyone else is around. Also, water and chapstick will be lifesavers when you’re under the lights and doing multiple takes.