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How to prepare a customer invoice
Write or type your company's contact information on a sheet of paper, spreadsheet or other electronic record keeping system.
Remember to include an email address and phone number where they can contact you with questions.
Create an original customer invoice number using letters, numbers or both.
A customer invoice number can be as simple " job-001 " or more complex, such as " smith-job-001. " the second example is useful for repeat customers because it includes their last name along with a job number.