For presentations intended to educate or persuade people in a professional setting or under other formal situations, it's a good idea to follow these tips:

• Keep the number of slides to about six. State the problem, the solution, the alternatives rejected, the research to support the solution, the cost (budget/resources), and action items. Title slides and a last slide labeled "Questions" can be included in the slide deck, but the body of your talk should comprise about six slides, no more.
• Try to keep each bullet point to one line in length, without text wrapping. Doing so aids readability and makes a list of bullets neat and scannable. Remove articles such as "a" and "the" if possible.
• Choose an appealing design template that is professional and not too eye-catching after the first slide. You don't want the design to detract from your message.
• Keep your slides accessible where possible. Use high contrast between background color and text color. For example, though a violet background with grey or white text is soft and approachable, you should avoid it, because people may have trouble reading it.
• Keep your text simple. Text on a slide primarily is a data point for you to key off as speaker. Effective slide text is not confusing and keeps people turning from each slide to you for more information. If you observe people focusing on your slides, the slides may contain too much data or be confusing or distracting in some other way.
• Ask your audience to hold questions until the end. Questions are an excellent indicator that people are engaged by your subject matter and presentation skills. But if you save them until the end of the presentation, you will get through the material uninterrupted. Also, early questions are often answered by ensuing slides and commentary.
• Stay on time! If your allotted time is 10 minutes, do not go over. If there's no time limit, take less time rather than more to ensure that people stay engaged.