The simplest way to find out what the audience wants is to ask in advance. If you are invited to present, take time to find out what the audience is expecting from you. Ask the individual who invited you. For example, if you are making a sales presentation, ask what kinds of features and benefits are most likely to be appealing to your audience. Does it want quality, efficiency, cost, or all of these?
If you are speaking to an internal group, find out what its issues are and find a way to weave those issues into your presentation. When you touch the concerns of the audience, you demonstrate that you understand its needs. Another means of determining audience expectations is to talk to people who will be in the audience. Find out what is on their mind. Think of ways to relate to their concerns without compromising your message.