Open Adobe Acrobat Pro
Open the PDF you want to make fillable
Go to Tools
Select Prepare Form
Choose the PDF file if prompted
Click Start
Let Acrobat detect form fields automatically, or add them manually
Use the form field toolbar to insert text fields, checkboxes, radio buttons, dropdowns, and signature fields
Drag and resize fields as needed
Double-click each field to edit its properties
Set field names, tooltips, and formatting options
Save the PDF
Test the fillable form by opening it and entering data
Make any needed adjustments and save again