If you’re having trouble because your text doesn’t fit correctly within the body or title placeholder text boxes, you can have Keynote automatically shrink it for you so that you don’t have to figure out what size to make it to make it fit. When there’s too much text in a box for it to be seen, a clipping indicator appears as a small plus sign (+) within a box at the bottom of the text box.
First you must select the text box that contains the text you want to shrink.
Double-click the clipping indicator at the bottom of the text box.
In the format bar, select the checkbox labeled “Auto-shrink.”
Hold down the Control key while clicking the text box, and choose “Auto-shrink Text.”
In the Text inspector, select the checkbox labeled Automatically Shrink Text.
The amount that the text was shrunk to fit in the box is displayed next to the checkbox in the Text inspector.
When you auto-shrink text, its font and line spacing are adjusted as required to fit within the text box; any specific line-spacing or font size settings you’ve made to the text are overwritten. But Keynote won’t shrink the text by more than 40%; if the text is still too large to fit in the text box after being shrunk by 40%, clipping will occur again and you will have to reduce the amount of text in the box, reduce its font size, or change its font to make it fit.
If you copy text from a placeholder text box that had auto-shrinking applied, and paste it into a text box without auto-shrink, the text will appear in its original size. If you paste text into a placeholder text box where auto-shrinking has already been applied, all the text in the text box is readjusted to fit within the box.
You can apply auto-shrink to the placeholder text boxes on a slide master, and that quality is inherited by any new slides based on that master. To learn about modifying slide masters, see the topics under Designing Master Slides and Themes.