Step-by-Step Guide to Adding Watermark to PDF on MacBook
1. Open the PDF document you want to watermark using Preview on your MacBook. 2. Click on the 'Tools' menu and select 'Annotate' > 'Text'. 3. Type the text you want to use as a watermark and adjust the font, size, and color. 4. Drag the text to the desired location on the PDF. 5. Save the document to apply the watermark securely on your MacBook.