In order to edit a form in Acrobat, open the form editor tool. In Acrobat DC go to Tools > Prepare Form. In earlier versions of Acrobat, go to Tools > Forms > Edit.
Acrobat Form Field Labels
Once the form field editor is open, existing form fields will be highlighted within the document. The form field labels will appear inside fields. Check these labels to make sure they are descriptive. In the example below, you can see that the Student Name field matches the label.
If the label does not match, double-click on the label to edit it. In the Text Field Properties dialog box that appears, edit the Name field.
Acrobat Form Tab Order
Once your labels are correct, check the tab order. Keyboard and screen reader users will use the Tab key to jump from one field to the next, and this needs to happen in a logical order. To see the tab order, click on the drop-down menu icon next to "Fields" in the Form toolbar (Acrobat DC). Select Show Tab Numbers.
Now you should see numbers inside of each form field that tell you the tab order. In the screen shot below, the logical order for the check boxes is mp3 (6), PDF (7), then Daisy (8). With the current incorrect tab order, it will be read as mp3, Daisy, then PDF.
To fix the tab order, select the PDF label on the form. This will also select the correct label in the toolbar on the right. In the toolbar, select and drag "PDF" upwards into the correct position between mp3 and Daisy.