If you’re like me, one of the first things you’d change if you were elected Emperor of Everything is having to sign documents and return them through e-mail. I used to find it very frustrating to print forms, sign them, and scan them back in. With Lion, though, Apple has benevolently provided us with an easy way to create multiple signatures and add them to PDFs with a couple of clicks, which will save a lot of trees and headaches. And I didn’t even have to become a supreme ruler to make it happen. Here’s how you can save your own and pop it into any PDF you want.

First, open Preview (it’s in your Applications folder), and then choose Preview > Preferences. You’ll see several tabs across the top of that window, and the one you want to choose is labeled “Signatures.” 

Before you go to the next step, grab some white paper. Anything will do—a sheet of copy paper, a blank page at the end of a book, or even the back of a check you’d like to sign over to me. Autograph the paper with a black pen, and you’re ready to move on. Click the “Create Signature” button, and we’ll do just that.

Here’s where the fun begins. Your Mac will show the view from your iSight or FaceTime camera, and you’ll need to hold the paper you’ve just signed up to the camera until your signature rests on the blue line in the Signature Capture window. If you don’t get it exactly right the first time, just pull your paper back from the camera and align your signature on the blue line again, and Preview will retake the image.

Here’s where we find out how terrible my cursive is. I’m sorry, Mrs. Bickerstaff.

When you’re happy with the results, click the Accept button. You can save multiple signatures if you ever need to sign something, say, with your spouse’s John Hancock. But you must promise to only use that power for good.

Now to add your newly created signature onto a form. To do so, open a PDF into Preview, then click on the pen icon (indicated by the red arrow in the screenshot below) to show the Annotations Toolbar (blue arrow).

After you’ve done that, you’ll see a series of icons, all of which you can hover over with your cursor to get a tooltip on what they’re for. The one you want looks like a capital S signed on a line.

Select that, and your cursor will switch to crosshairs. Click and drag to insert and size your signature any way you’d like.  

After you’re done putting your signature in, you can drag it around to change its position or use the familiar image resizing handles to adjust it again until it looks perfect.

Also, if you click and hold on the toolbar signatures icon, you can choose from multiple signatures if you have them or even create and manage signatures without going through the menus to do so.

Note that this will only work with PDFs; if you show the Annotations Toolbar on any other type of file that Preview can work with (like JPEGs or TIFFs), you won’t see the icon to insert a signature show up at all. So if you get a file that you need to sign and it’s in another format (Microsoft Word, anyone?), just export it as a PDF to be able to sign it within Preview. Isn’t that cool? Now if we could only do something about the folks who want us to fax stuff, we’d be golden. That’s next on my Emperor to-do list.