Open your Google Docs document and navigate to the top menu bar.
Click on "Format", then scroll down and select "Line & paragraph spacing" from the dropdown menu.
A list of spacing options will appear. Click on "Double" to apply double spacing to your document.
If you want to double-space only a specific section, first highlight the text before selecting the spacing option.
Once applied, your document’s text will automatically adjust to double spacing throughout the selected area.
If needed, revisit the "Line & paragraph spacing" menu to customize spacing further.
Finally, review your document and save your changes to ensure the formatting is applied correctly.