This article tells us how to design of invoice. The following steps as below:
Step 1. Go to 'Outlets' - click 'B1' on Column Receipt Template

Step 2. Outlet - tab Receipt Template - Fill the section
(Width: <= 8cm)'
Note : if you want customize paper size please follow this article

Step 3. Choose A4 Print Type if you are not using thermal

Step 4. Go to Invoice Note (term & condition) - Update
