A man in boots looks ridiculous on TV unless the boots are the same, dark color as his pants. Women have more choice of color than men. Most shades of blue are flattering to everyone. Other good choices include coral and aqua. Those with dark hair look good in bright green, deep burgundy, and bright purple.
Blondes can look wonderful in gold or rust.
Don't refuse TV make-up. The brights lights wash out facial color, and make even the healthiest person look pale and ill. In addition to what you say, and how you dress, don't forget body language. If your hands tend to move nervously to your face, hair, or pockets, give them something to do. This will relax you, open your throat, and help you appear composed.