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How to add your signature to digital forms and documents in macOS

In the event a digital document needs to be signed, like a form or a letter, macOS includes a way to add your signature without needing to print out the pages and rescan them. AppleInsider shows you how to quickly and easily sign PDF documents on the Mac.

Signatures continue to be an important part of everyday life, ranging from use as authorization or confirmation on a forum or contract, or to add a personalized touch to a letter. In the digital age, with documents often sent over email or downloadable from websites that require signatures, this can cause an issue.

While some people will go through the process of printing out the relevant page then sign the document in ink before scanning it back in to send, this can be a lengthy process. Scanning in a signature is another method that allows for it to be reused multiple times, though you still have to clean up the image to make it usable to start with, and keep track of where the file is kept.

The method included in macOS is relatively quick and painless, needing either a trackpad or a webcam, along with Preview.

Creating the Signature

Open up the document PDF or image you want to use in Preview. In most cases simply opening the file will bring it up in Preview by default, but if this is not the case, right-click the file, select Open With, then Preview.

You can also open Preview from the Applications folder, then select File then Open in the menu, select the file you want to open, then click Open.

Once the file has opened, click the Markup toolbar icon on the right-hand side of the window's menu, which looks like a pen nib in a circle. Within the Markup toolbar, select Sign, the one that looks like a signature on a line with a dropdown arrow next to it.

If there are no existing signatures on the list, the Sign box will immediately offer to create a new signature using either a Trackpad or Camera. If neither option is available, it will instead warn that one of the two is required for the process.

To use the trackpad, select the Trackpad option then use a finger on the MacBook's trackpad to write the signature, clicking clear if there is a mistake. Once finished, press any key to regain normal use of the Trackpad, and click Done.

Alternately, select Camera to turn on your Mac's webcam or the MacBook's iSight camera. Take a white sheet of paper and sign your name in black or very dark ink, then hold the page up to the camera so the signature lines up with the on-screen line.

The Mac will then overlay its detected signature on top of the camera feed, with mistakes able to be removed by clicking Clear. Once the signature is satisfactory, click Done.

The new signature will appear as an option in the Markup toolbar's Sign function.

Signing the Document

With the file you want to sign open in Preview, click the Sign button in the Markup toolbar to bring up the list. Click on the signature you want to add.

This will place a version of the signature in the middle of the Preview screen. Drag the signature to the place it needs to go, resizing if required.

Once it is in place, save the updated document by selecting File then Save in the Menu.

Signing Documents in Mail

For items that need a signature that arrive through email, it is a relatively similar process.

Click Reply to respond, then click the Include attachments from original message button.

Hover the mouse over the document and click the dropdown arrow in the right-hand corner. Select the Markup option.

In the new window, select the Sign icon at the top, and select the signature you want to add. Rescale and move the overlaid signature into the right location on the document, and click Done.

This will update the attachment in the reply email. Make any other needed adjustments to the message, and click the Send Message icon.

Removing signatures

If you want to remove any signatures stored on the Mac, this can be done by navigating to Sign in Preview's Markup options and clicking the X circle on the right.

Further notes

If you have multiple Apple devices signed into the same iCloud account, signatures you register can be synchronized with them as well, so you only have to create one for use on all of them. It is possible to set up signatures on an iPad or iPad Pro, which will also be available to use on the Mac.

There is also the option to set up multiple signatures on an account. This means you can set up various signatures for different situations, such as a standard surname and initials for forms, and a full name version.