In some presentation slides, the grid is obvious: a data table is an example. But also without the explicit lines of a table structure, you can recognize a grid in almost any composition you make. A diagram, the positioning of boxes on a slide, even a big picture with a few words of text. Recognize the grid structure, imagine the hidden lines and make sure everything lines up and is spaced out nicely. It will make for a much better slide composition.
If you are ready to dive in to hard core literature on the use of grids in graphics design, I can recommend the 1981 book Grid Systems (affiliate link) by Swiss graphics design master Josef Mueller-Brockmann (some of his poster design are in this Flickr set). The big issue for print designers is to juggle around text columns and images. Presentation slides are a bit different, but still the conceptual approach applies to them as well.
If you are ready to dive in to hard core literature on the use of grids in graphics design, I can recommend the 1981 book Grid Systems (affiliate link) by Swiss graphics design master Josef Mueller-Brockmann (some of his poster design are in this Flickr set). The big issue for print designers is to juggle around text columns and images. Presentation slides are a bit different, but still the conceptual approach applies to them as well.
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