That is very simple if you have the free Adobe Reader XI. If you have an older version, you need to upgrade to version XI: Older versions of Reader will not let you modify the document.
Once you have the free Reader XI, click on the "Fill & Sign" item on the right side of the Reader user interface. This will show the "Fill & Sign" pane, which should look like this:
You can now select the "Add Text" tool and start typing on the form where you are required to enter information. If you need to adjust the text properties, you can bring up the "Add Text" properties toolbar using Ctrl-E or Cmd-E on a Mac.
As you can see, there is also a "Add Checkmark" feature on this pane that allows you to place a checkmark in a checkbox. To adjust the sized of a checkmark, place your cursor over one of the drag handles, then click and drag that corner until your checkmark is correctly sized:
Karl Heinz Kremer
PDF Acrobatics Without a Net
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