The hours are extremely irregular, so I have a problem distinguishing between night and day. Presentation is about being comfortable in front of a camera. My communications major has helped me with the background to television. Writing and being able to communicate with an audience you cannot see are very important. I would say that communications and journalism are two very important courses to help one understand audiences and their needs.
Computer literacy is also essential.
Punctuality is number one on the list. People expect you to be the same off air as when you are on air. Audiences love presenters to be human so they can identify themselves in you, so it's important not to allow the glamour of television to take over your character. You are what you are because of the people - thank them for it, and they appreciate you for it. Humility is the key, not attitude.