Use a digital format – Using a digital format is one way to ensure your invoice is professional, and to indicate that you're likely to use the latest tools, and follow best practices, on the job. Simple mobile apps like Invoice2go will allow you to create and send professional estimates and invoices on site when the project is still fresh in your client's mind. These apps can even store receipts so you have a real-time way to keep your expenses organized for easy presentation to your clients.
Terms (or Payment Terms): Invoice terms depend on common practices of your industry, your relationship with the customer, and your cash flow needs. For example, “Net 30” means that the invoice is due 30 days after the Invoice Date. Be mindful some businesses may pay later than the stated due date, so you may want to include a buffer to keep your business free from a cash flow gap.