Either select a pre-made set of margins or choose "custom margins"

Selecting "custom margins" will open a window with multiple editing options including margin sizes on each side of the paper, whether the sheet should be centered horizontally or vertically on the page, and print preview using the custom margins changes.

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This guide provides step-by-step instructions on how to modify page setup in Excel. It covers various aspects such as changing margins, page orientation, sheet size, printing tiles, and using the page break preview. By following these instructions, users will be able to customize their Excel sheets for optimal printing and viewing.