This setup to display the signature on invoices which are usually used for Delivery order, in this setup you can use two to four signature fields.
I. How to Visible Signature
Step 1. Go to Setup Menu - More Menu - Printing Configuration
Step 2. Click General - Visibility - Signature Visible - Yes - Save
II. Setting and Rename Tittle Signature
Step 1. In the section Printing Configuration - Click (Tab) Customer Invoice
Step 2. Scroll down select Signature - input the Column to match your Printing requirements
Signature with 4 columns.