When you convert an existing document into a PDF form, Acrobat automatically adds interactive form fields to the form. You can then edit the form to add specialized form fields, such as a drop-down list, list box, or buttons.

A. Certificate-based signature field
B. Drop-down list box
C. Text fields
D. Automatic message bar
E. Check boxes
F. Radio buttons
G. List box
H. Buttons 

1. Choose Tools > Prepare Form.
2. Select one of the following options:
   1.  Single file - Converts an existing electronic document (for example, Word, Excel, or PDF) to an interactive PDF form.
   2.  Scanner - Scans a paper form and converts it to an interactive PDF form.
   3.  Create New - Start creating a form from scratch with a blank page. For more information, see How to create a form from scratch.
3. If you want others to sign this form, select the This Document Requires Signatures check box.
4. Click Start. 

   Acrobat creates the form and opens it in the Form Editing mode. The right pane displays options for editing the form. The toolbar contains form field tools for adding additional fields.
   

5. Review the form fields Acrobat created. Add fields using the form field tools in the toolbar. Delete, resize, or arrange the fields as needed. You can add any of the following types of form fields:
   1. Add Text field - Add text to the PDF document.
   2. Barcodes - Encode the input from selected fields and display it as a visual pattern that can be interpreted by decoding software or hardware (available separately).
   3.  Buttons - Initiate a change on the user’s computer, such as opening a file, playing a sound, or submitting data to a web server. These buttons can be customized with images, text, and visual changes triggered by mouse actions.
   4. Check boxes - Present yes-or-no choices for individual items. If the form contains multiple check boxes, the user can typically select as many or few of these as wanted.
   5.  Date field - Lets the user enter a date in the PDF document.
   6.  Digital signature field - Lets the user electronically sign a PDF document with a digital signature.
   7.  Drop-down list - Let the user either choose an item from a pop-up menu or type a value. You can set a form field property that enables the user to enter a custom value.
   8.  Image field - Adds an image field. Allows user to browse and select the image to add to the PDF document.
   9.  List boxes - Display a list of options the user can select. You can set a form field property that enables the user to Shift-click to select multiple items on the list.
   10. Radio buttons - Present a group of choices from which the user can select only one item. All radio buttons with the same name work together as a group.
   11. Text fields - Let the user type text, such as name, address, or phone number.
       For more information, see How to add form fields and set their values.
6. To change existing text or images, click Edit in the toolbar. All the text and image fields are enabled for editing.
7. To test your form, click the Preview button in the toolbar. Previewing a form allows you to view the form the same way the form recipients will and gives you a chance to verify the form. If you are previewing a form, you can click the Edit button to go back to the edit mode.
8. When your form is complete, save the form, and then click the Close button towards the right end of the toolbar to close form editing.