1. Click on the Invoice project button and the Client Jobs of that project will be added to a new client invoice

This will pop up a new add/edit invoice window:

The system will add the default data to the invoice to save you time - these include the client, the client PM, the sale tax rate, the default template and payment terms of the client.
1. In the Add/Edit Invoice window fill in the invoice details
2. Add a custom Payment due date/Date Sent/Date due if you want to override the client payment terms that you specified on setting up the client
3. To add an additional charge (surcharge) enter the %age to add a discount enter a negative %age e.g. '-10%' and click save to update the total
4. To add other client jobs from other projects click the Add Job button