2.) Your slides should NOT be a transcript of your speech with every point and sub-point. In other words, "you don't need to put all the dang words on the dang slides." I can't recall whose quote that is, but you get the point.
3.) In my experience you should always use at least 24-point type. Otherwise there will most likely be a number of people at the back of the room that can’t read your slides. If people can’t read the text on your slides, why have the text on the slides?
4.) Avoid detailed charts and graphs like the plague. If you must show a detailed chart or graph, hand it out as a full page print out. Don’t force people to try to read it on a slide. Better yet, have a slide with only the key figure or fact you want people to take away from the chart or graph.
5.) You can only convey so much information in a 20 to 30 minute presentation. Your audience will recall much less than that. The less you convey, the higher the recall – meaning the more effective your presentation. If you have a lot of supporting data, scientific data, charts and graphs, then you should prepare a white paper and upload it to your website. Then during the presentation, let the audience know that they can find the more detailed information in the white paper on your website.
There you have it. And, like most good presentations, the above rules have some repetition, or reinforcement, with number five more or less reinforcing the first four rules. So really just four simple rules to follow. That's not too much to ask, is it?