However not everyone knows how to make the image, it's really easy though.
As a suggestion I wouldn't save this image anywhere but a personal flash drive or in a password protected folder, since it could be used to help falsify your identity. You could sign it differently from your written signature and keep track of when you used it, you'll always know which is which and if you signed the document that way, plus if anyone gets the file they'll not be able to hand forge your signature with it.
- A scanner or camera with macro
- A pen and paper
- Photoshop or Gimp (instructions for both included)
- A PDF editor
Step 1: Write and Scan
Now if you're scanning, use black and white mode, I used photo preset but document will likely work fine too.
Save the file somewhere.
If you're taking a photo of the signature make sure it is in focus, evenly lit and from a perpendicular angle to the paper.
For the photo takers, use black and white.
Step 2: Open and Crop
Clean up any dirt marks with a white brush.
For photoshop use the crop tool (c) and pull the box down around the signature you want, rotate as needed.
For gimp use the selection tool then go to image>crop to selection
Step 3: Removing the Background
Choose the background eraser tool and select discontiguous mode, click on the white and drag the eraser around until all the white is replaced the transparency, you'll see grey and white tiles, that's the default background. You can also choose the magic eraser and just click on the white.
In Gimp, you'll need to right click the background layer and hit add alpha channel.
Now right click>select>by colour and drag on the white. Hit delete or right click>edit>clear.
Your image should now have a clear background and you'll see gray and dark gray tiles behind the signature.
Step 4: Saving the File
Instead we save it as a .PNG format.
In photoshop click file>save as, choose PNG from the drop down list
In gimp choose to save the file, click the select file type pop up at the bottom and choose PNG from the list.
The standard settings should be right for this.
Step 5: Signing the Document
In acrobat import the image as a stamp, then add it to signature boxes.
For others it might be easier to add as an image, some have a signature function where you choose an image and it keeps that as your signature.