Invoices & Receipts:

Navigate to settings -> Documents -> Invoice Receipt.

From here you will be viewing all the invoices and receipts

Step 1:
Edit:
By hit on Edit, You can edit the invoices as display below

Step 2:
For example, You have planned to remove the Email ID all you need to do is unselect the item and click on save & preview. To view the updated changes.

Step 3:
As you can see from the above image, the Email Id has been disabled.