Select existing template to modify (circle number 2 on the screenshot below) or
set-up a name for a new template (circle number 4 on the screenshot below):
Use auto-replacements (circle number 3 on the screenshot below),
set-up currency symbol, round down amounts and total, last invoice number (circle number 5 on the screenshot below):
Click on the save button.
Everything from timesheet page will go into the invoice.
Select or unselect projects/boards that should be listed on invoice (circle number 1 on the screenshot below)
Check additional data that will go into invoice (circle number 2 and 3 on the screenshot below):
Add and fill in additional items and amounts
that you need to be added to the invoice (circle number 4 on the screenshot below):
Select invoice template
to generate invoice and click on the Get Invoice PDF/Get Invoice Excel button (circle number 5 on the screenshot below):