Slide Tips: fix your design
Just because it came pre-installed in your computer does not make you a PowerPoint expert by default. Building a presentation is a lot of hard work. Don’t expect to become an expert in one go. It will take time for you to understand how to use the tool and how a great slide should look. Please find below a few tips to help you build effective slides. Give them conscious thought to ensure that your slides are the best they can be.
Keep it simple

Simplicity rules. Don’t let your message and your ability to tell a story get distracted by slides that are unnecessary cluttered and complicated. Nothing in your slide should be superfluous, so trim extensively. Most likely your slides will require several rounds of ‘trim & redo’ before you achieve that slide with the absolute minimal amount of information required to convey your message. Use plenty of empty space. Just as remaining silent at times in a conversation is a great quality improver, so is withstanding the urge to ‘do’ something with empty spaces. The less cluttered, the more powerful your message will become.
A proper lay-out matters

Lay-out is important. Depending on the use, you must fine-tune your lay-out. Feel free to be creative, but don’t overdo it! A basic, sure-fire lay-out is as follows. Use the top row to make the point of your slide. If it needs to be written down, then use a compact sentence, not just a single key word. Then, data goes on the left, and an explanation what that data entails on the right. So, a chart on the left, explanatory points on the right. This has to do with the way your eyes are wired to your brain. The right brain is the creative side, the left brain the analytical side. However, your optical nerves are crossed: right eye goes to left brain and vice versa. Hence, the image on the left, and the analysis on the right.
Consistency, consistency, consistency

Once you decide on a lay-out, use it consistently throughout your slides. It irritates and confuses your audience if your slides change ‘style’ all the time. Consistency also goes for the use of fonts, colours and the like. Learn how to use the master templates in PowerPoint (or Keynote) and make the required changes there.
Become pixel-perfect in everything

Learn to use the snap-to-grid and snap-to-shape and align tools in PowerPoint (and the guides in Keynote). Make sure that objects are in a pixel-perfect spot. A line connecting another but shifted even one pixel will be seen by your audience. It will be viewed at as sloppy, and so will thus be viewed you and your arguments. So zoom in and make sure that everything on your slide (and between slides!) is pixel-perfectly placed.
Use a bread-crumb trail

As you will tell them what you will tell them, and then tell them, it works wonders if you aid your audience in where they are in your presentation. More often than not, other important people will enter your presentation a few minutes late. They will have missed your explanation of what you will cover. So help them using a visual guide, a bread-crumb trail, that depicts in a simple but effective way where the individual slide sits in your story.
Limit bullet points and text

Boring an audience with slides riddled with bullet points is of very little benefit. Use texts sparingly. But when you use it, use it in a concise fashion. Depending on the use of your presentation, the amount of text you use can vary. Again, simplicity rules here. Some slides will be able to convey the message with a graphic only. However, they will be virtual meaningless without your narration. Which brings us to hand-outs.
Hand-outs are a vital part

Don’t just print your slides and hand them over. Use this opportunity to reinforce your message by adding additional narrative comment, arguments, opinion etcetera in what is called the ‘speakers notes’ in PowerPoint (it should have been called the ‘audience notes’, really). And, coincidentally, now that you know that you have a fine opportunity to serve your audience with additional information through a hand-out, you may feel less inclined to add all that detail on the slide itself.
Limit transitions, builds and animations

Just because this functionality comes with the software does not mean that you have to use it! It is highly distracting and irritating for your audience if text or graphics zoom or twirl in any which way whilst appearing, with a different style on every new slide. Just refrain from using it. And if you feel you must (which really is only if there is an explanatory need to do so), then be consistent in the one you pick (‘dissolve’ will almost always suffice). Same goes for transitions between slides. A simple fade through black or dissolve will be more than adequate.
Use high quality graphics

Use high-quality graphics and photographs. Take your own picture with your digital camera, or use one of the excellent stock photography websites available today. Avoid the usage of PowerPoint ‘clip-art’ at all times. They will be perceived as cheesy and unprofessional. Clip-art may have been a big thing 15 years ago, but today audiences will expect you to come up with professional looking graphics. If you feel you cannot produce high-quality imagery yourself, then consider hiring someone that does.
Avoid PowerPoint templates

You obviously will need a visual theme in your presentation. But the same argument that goes for clip-art goes for the built-in templates in PowerPoint. Your audience will have seen them countless times. They expect a unique presentation from you, and that goes for the visual theme as well.
Use colour well

Colour is highly important. Colour invokes emotion, feeling. The right colour can help persuading and motivating, whereas the wrong colour can do exactly the opposite. It pays if you study the usage of colour a bit. Colours can be divided in a few primary and secondary colours. Some are called cool colours (like blue), some warm (like orange). Cool colours work best for backgrounds, as they appear to recede into the background. Warm colours work best for objects (like text) in the foreground as they appear to be coming towards us. So orange text on a blue background works. However, you must consider the fact whether you are presenting in a light or a dark room. If it is dark, then use cool and warm colours as said. But if the lights are on (and this is highly advisable), use a white background with dark text as this will hold its intensity much better that a cool background with warm text, which has a tendency to wash out in ambient light.
Use fonts well

Choose your fonts deliberately. As with colour, it pays to make a bit of a study of fonts. The font you choose will convey subtle messages in themselves to your audience. Choose no more that two complementary fonts in your presentation, and use them consistently (one for headings, the other for text). Serif fonts were designed to be readable when using large amounts of small text. For presentations, a sans-serif font usually works better. Also remember that many people in the audience will most likely have glasses, maybe only for reading. Facilitate the readability of your slides by choosing a big enough font size, and test whether your slides are readable by moving to the back of the room during your trial runs.
Include video or audio

Use video and audio when appropriate. People are visual animals and using high quality video clips stimulates active cognitive processing, which is the way people learn. Same goes for audio. But remember to -only- use them when appropriate, not just to show off. You can import video and audio files easily into PowerPoint (or Keynote). Using video or audio will also help in increasing the interest of your audience, as the change of pace will be a welcome break. Whatever you do, do not use the sound animations that come with PowerPoint. As with clip-art and templates, they may have been fun in 1990 but not anymore. Adding these cheesy sound bites to slide transitions or animations is a sure way to make you look unprofessional to your audience.
Use the slide sorter

Spend time in the slide sorter. It will help you get a quick overview of the material that you have and how your presentation is progressing. It will make you ‘see’ the structure, the logic of your presentation far better than going page-up and page-down in your presentation. Thus, you can see the nature of your presentation from the point of view of your audience. It will help you notice flaws in the logic of your arguments and any superfluous bits of data quickly.