A slide presentation should tell a story, often chronologically. The first slide should contain the title of your presentation, just like any other publication. Using an introductory slide to provide an overview of your talk can help the audience to understand the big picture, similar to a table of contents. It will also help you to present your material in the most logical order. The middle slides contain the main content, and the last few slides can include a summary of your talk, and any acknowledgments or contact information.
Keep to 1 idea per slide. Include a heading for each slide, which can serve as your cue as well as informing the audience. Think carefully about the heading and use it to describe briefly what that slide is showing:
Instead of:
Survey results
use:
The most popular flavour of ice-cream is vanilla or Chocolate and strawberry are equally popular
Instead of:
Water-efficient practices
use:
Saving water in the kitchen or Saving water in the bathroom
If your talk is longer than 30 minutes, or covers different subtopics, consider using section slides. These are slides with just a subtitle on them to separate your topics, just like different chapters in a book. This can help to keep you and your audience focused.