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Open the PDF document or form in Acrobat or Acrobat Reader.
Click Fill & Sign in the right pane, or click the Fill & Sign in the toolbar.
The specific tools and options for Fill and Sign are then displayed in the toolbar. Use them to fill out your form:
Using Typed Annotations
Click the "Add Text" button, then the location on which you wish to sign the form. This will generate a text box in which you can type your name, along with some basic buttons that will allow you to change the size of the text or delete the text box entirely. 
Clicking outside of the text box will exit it , while clicking on the text again will allow you to re-enter and edit the text already entered. Once this document has been saved and sent to another user, the text box will be locked and uneditable for new users.
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