Use Form 1040X to amend your original Form 1040, 1040A, or 1040EZ. If you prepared your 2010 tax return using our product, we'll fill in most of the form for you automatically.
To complete Form 1040X, proceed as follows:
Load your originally-filed tax return.
Save a copy under a new name (File/Save As).
Make the corrections to this new file by going through the Interview.
Go to Form 1040X (this form) in the new file.