After important points look for the person's reaction to what you have just said. If the person feels like you have been talking to them, they'll nod. People nod when they have processed what you have just said. "Waiting for the nod" is an effective way of pacing your delivery to the rate at which your audience can take it in.
The most powerful time to have your eyes up is at the end of a sentence. Unfortunately, it's also the time when you'll be most tempted to drop your eyes so that you can look at your notes. Discipline yourself to keep your eyes up till you've finished your sentence, then look down. Look at your notes in silence. When you're ready to continue, look up, find someone to talk to and then start talking.
Eye connection means spending time with each person so that person feels like you're talking just to them. Eye connection has two major benefits:
1. People in your audience will feel that you have genuinely connected with them and that you care about their reaction.
2. Because you're talking to people as if you were in a one-on-one conversation, you'll come across as conversational. That makes you easy to listen to and engaging.
Some people in your audience may show that they're uncomfortable with eye connection by looking away. Different cultures have different norms regarding eye connection. Respect that by spending less eye connection time with them - but don't ignore them!
Shrink the room:
Imagine that the person you're looking at is the only person in the room. For those few seconds you're having a one-on-one conversation with just that person. This has two benefits. You're likely to talk in a more conversational style because you're drawing on the conversational skills you already have. It may also reduce your nervousness because you'll no longer feel like you're talking to this big audience - but just to one person.