I've talked a lot in the past about a principle that lies at the foundation of many of the business decisions I make: Only Do What Only You Can Do. The idea is that you should focus on the things that help you grow your business and make money, and find a way to have someone else do the rest.
One of the investments many photographers look at is bringing on a studio manager, which can be a huge help in managing the day to day aspects of your business. A good studio manager can help you with client communications, scheduling, invoicing clients, and more. In fact, depending on how much you are willing to pay, and the skills of the person you hire, you can create a position that handles many of the tasks you do everyday - leaving you with more time to focus on the things that grow your business (marketing, meeting new clients, photographing more events, etc).