I wish to change page borders

The page borders are currently too large for the work I am doing. I wish to make the smaller.

Choose Menu Format>Page and there the tab “Page”. In the dialog you can set the page margins.

Adding to @Hrbrgr answer, and in second place:

You can choose menu File - Print Preview (the same that Ctrl+Shift+O), then selecting the Margins button you can drag the margins lines.

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