DON'T LOSE YOURSELF! There are thousands of good tips on how to look good in photos and etc., but the most important tip anyone can ever give you is DON'T lose you're self!! :D
Also.... *Be on time it shows dependable-ness * Stick your chin out SLIGHTLY in pictures so it will diminish any double chin or anything. * Be original and never copy someone else! Just be YOU if you do well because of anything else it will be fake and make for an extremely difficult life.