Next you'll want to include your contact information: your mailing address, phone number, email address, website, etc., right underneath your business name. If you'd like to up the professionalism, create and include your own logo on the right – or left-hand side of the header.
Product or service details: Specify Description, Quantity, Rate, Amount and Subtotal. The more details you include on the invoice, the better. This way, your client will know exactly what they are paying for upon receiving the invoice. Make sure that your client can understand every item, so that as soon as they receive the invoice, they can pay you instead of asking questions and delaying the process.