Here's a tip when designing your slides: Stay away from the edges. By which I mean that you shouldn't put anything important near the four edges (left, right, top or bottom) of the slide as it may be cut off when the slide is projected.
This is usually a technical problem, for example when your laptop and the projector have different ideas about the resolution or aspect ratio. It's a good idea to arrive at the venue early so you can test and possibly resolve such issues, but sometimes you just have to live with them.
Wouldn't it be a shame if your carefully designed slide can't unfold its full potential just because of a small technical glitch?
In addition to technical problems where the slide is cut off at one (or more!) of the four edges, the bottom of a slide may not be visible for people in the back of the room if it's a "flat" room, i.e. when all seats are on the same level, so take that into account, too.
When we design a slide, we do that on our PC's screen where we can clearly see the entire content. It doesn't even occur to us that some part of the slide may not be visible to our audience. So when rehearsing for your next presentation make sure that not only is the content of your slides readable (using a large font and good contrast), but also consider how they would look with parts of them being obstructed or cut off.
(Image Credit: "Use Caution Near The Edge sign (yellow)" by the Grand Canyon National Park Service, from Flickr)
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