Everyday I see clients squinting at tiny slide images on their screens. No, you can't do anything about the physical size of your screen, but you can fix the window arrangement.
The most obvious adjustment is to make the PowerPoint or Keynote application as large as possible. But the aspect ratio of slides and its implications is often overlooked.
If you design 16:9 slides the width of your screen is the bottleneck, minimize menu bars on the left and right of your slide (format panels, slide icons). If you design 4:3 slides the height of your screen is often the bottleneck, minimize slide notes boxes.
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