You can also schedule your appointments to make it easier to keep your appointments. I currently use Calendly and even when a client called to book a coaching session this evening, I simply referred her to my scheduling app, so that I have everything in one place.
Your sales and accounting records can so easily be done for you by accounting apps such as Zoho, Wave or Paystack. Some software receive payments, generate receipts and invoices and even notify your customers when their bills are due for payment. This takes the burden off you and also increases accuracy (especially for those of us who do not particularly enjoy dealing with figures).
Tasks such as collecting data from your clients can also be automated and the good thing is that the tools help you to analyze them. I can readily think of Google Doc here.