How to do setup of which Bill Format send in WhatsApp, Mail?

Step 1) Go to Master > Nx Messenger > And select Messenger Setup
Step 2) Select Sales or Click on the right side Email option.
Step 3) After that click on the right side Email format option modified.
Step 4) Select the sales format which you want to send by mail and show that option above the right side.
Same like Whatsapp setup Format which sends an auto App.