To add a photo to a PDF, use a PDF editor tool that allows image insertion. Here is a general process:

• Open the PDF in a PDF editor (such as iLovePDF, PDFgear, Smallpdf, Adobe Acrobat, or pdfFiller).
• Look for an option in the editor like "Add Image," "Insert Photo," or "Add Stamp."
• Select the photo/image file you want to add from your device.
• Place the image on the desired page in the PDF, then resize or move it as needed.
• Save or download the edited PDF with the inserted photo.

Common key details:

• The image formats supported usually include JPG, PNG, BMP, TIFF, and GIF.
• Editing features usually allow resizing, rotating, and positioning the photo.
• Many online and offline editors offer this feature free and without needing to reprint or rescan documents.

For example, with iLovePDF:

• Go to their Edit PDF tool.
• Upload your PDF.
• Click "Add Image" and insert the file.
• Drag to position and resize it.
• Save the edited PDF.

With Adobe Acrobat (updated interface):

• Open PDF, select Edit > Image > Choose Image.
• Pick the image and add it.
• Resize or modify as needed.

This way, a photo can be seamlessly integrated into any PDF document without extra printing or scanning steps.