Step1: Click on the second tool of the toolbar at the left corner of you page reading 'Products'
Step2: Each product has tool attached to it. Second tool with pencil icon reads ' Edit tool'. Click on it to edit the product details.
Step3: Choose ' Pricing' tool.
Step4: Click 'Edit' under would you want to customize the invoice of your customer?
Step5: Customize your invoice in the indicated section and also feel free to choose logo for your invoice.
Step6: Click on 'Save'. With this invoice for your product will be updates successfully.