When you receive a digital contract or a lease agreement via email, the old-fashioned process of printing the document, signing it with a physical pen, and scanning it back into the computer is a massive waste of time and paper. If you use an Apple computer, you already possess a built-in cryptographic signing tool. The macOS Preview application allows you to generate a perfect, digital copy of your handwritten signature using your trackpad or your Mac’s webcam, and seamlessly stamp it onto any PDF document.
How to Create a Digital Signature
Before you can sign a document, you must capture your signature and save it into the macOS system.
- Double-click your PDF document to open it in Preview.
- Click the Show Markup Toolbar button (the pencil tip icon) in the top right corner.
- On the new horizontal toolbar, click the Sign icon (it looks like a small cursive signature).
- Click Create Signature.
You now have two options to capture your signature:
- Trackpad: Click the “Click here to begin” text, and literally use your finger to trace your signature directly onto the glass of your Mac’s trackpad. Press any key on the keyboard when you are finished.
- Camera: Write your signature on a blank piece of stark white paper using a thick, black marker. Hold the paper up to your Mac’s FaceTime webcam. The software will instantly identify the ink, extract the signature, and vectorize it onto the screen.
Click Done. Your signature is now permanently saved to your iCloud account, meaning it is instantly available across all your synchronized Mac devices.
How to Sign the PDF Document
Now that your signature is saved in the system, signing the actual contract takes less than two seconds.
- Ensure the Markup Toolbar is open and click the Sign icon again.
- You will see a small preview of your saved signature in the drop-down menu. Click it.
- The signature will instantly drop directly into the absolute center of your PDF document.
Your signature behaves exactly like a digital sticker. You can click and drag it to the exact signature line on the contract. If the signature is too large, click the blue boundary handles on the corners of the box and drag inward to mathematically scale the ink down to the perfect size.
When you are finished, press Command + S. Preview will permanently flatten the signature directly into the PDF layers, ensuring the contract is legally binding and ready to be emailed back.