The best thing about using an invoice system is that you can track your time against the amount you're getting paid for each task. In order to run a successful business, you want your hourly rate to be profitable so you're not losing time and money. Another benefit of using an invoicing system is that you'll never save over an invoice and lose the work you've calculated for another client.
Track your time each step of the way – Time is money, so it's vital to keep track of it. It will also help you learn how long it will take to complete similar future projects. This will facilitate a better work schedule so you can tackle more jobs. Accurate time tracking will add more transparency to your billing and will help clients know what to expect when they need you to work on similar tasks later. Use time-tracking mobile apps so you can clock in and clock out right there on the job and not have to estimate your work hours once you're done.