Here's a problem that happens all too often. Someone sends you a PDF that needs your written signature and a date, but you want to be able to fill it out without having to print it, fill it out, and then scan it back into your computer. Many times, editable PDFs will have form fields that you can simply click and fill out online. However, even if it's just a static image PDF, you can still complete it without using a printer or scanner.

As you might expect, this task is easiest on a Mac with the Preview application for viewing images and PDFs. The first time you add your written signature to a PDF, you'll have to perform a few preliminary steps, but after that, it's easy. This how-to will focus on adding a signature, with a few words about typing in your name and date. For those more comfortable with Adobe software, we also cover how to add a signature in Adobe Acrobat Reader.

Take a Picture of Your Signature

Start by writing your name on a sheet of white paper, preferably with a dark felt-tip pen, then open your PDF in macOS's Preview. Open the Markup toolbar by clicking the button immediately to the left of the search field (or click Show Markup Toolbar on the View drop-down). Click the icon that looks like a signature to activate the Signature tool, then click Create Signature.

At this point, you'll have the option to make a signature using your computer's touchpad or take a picture with the camera. We recommend the latter for its accuracy. Just click on the Camera tab to open a view from your camera. Hold your written signature up to the camera and make sure it aligns with the onscreen guideline. Click done to take the picture and a tiny image of your signature will appear on the Signature menu.

Apply Your Signature Using the Mac Preview App

Now simply click on that image, and your signature will appear in the PDF file, ready to be moved and resized until it's exactly where you want it. The signature image is transparent, so the text and boxes on the PDF will remain visible beneath it. Save your document, and just like that your signature is now baked into the PDF file.

If the computer is used by several different people, or you need to sign a form on the behalf of someone else, you can store multiple signatures in Preview. Click on the Create Signature button in the Signature tool and add any signatures you need. You can delete existing signatures by clicking on the delete button to the right of the thumbnail image, or use Tools > Annotate > Signature > Manage Signatures.

How to Edit Your PDF

To type your name, date, and information into the PDF, go back to the Show Markup Toolbar and click on the Text tool. A box with the word "Text" will open in the middle of your document; drag it into a blank area on the page, select the word "Text," and replace it with whatever text you actually want to add to your PDF. Select the text you typed and click on the Text Style button and change the font, size, and color as desired. Then drag the box to where it belongs in your form.

The major gotcha in this procedure is that the text you typed is a PDF comment, and it can be changed or removed by anyone who opens the file. If you want to bake the text permanently into the PDF, use the roundabout method described at the end of our how-to guide for editing PDF files.