Go to http://www.festisite.com/text-layout/ and choose Rebus from the menu on the upper right.
Note the text box with pre-written nonsense. You will replace this with your own typed or copy and pasted text.
From the menu at the bottom of the box choose a font, font size and switch the Paper from a4 to Letter.
Your rebus box should look like this:
Click on Layout Text to see your Rebus:
Here is a new rebus site that is tricksier http://www.myrebus.com/create
Click to Enlarge the Rebus!
You'll never get this one, and not just because it is tiny. Merry Christmas!