Dear Left:
As wrong as this is, it will always be a problem. Clients that make appointments and don’t show are inconsiderate! If this is a first-time customer, there is very little you can do other than tell her your cancellation policy when she makes her next appointment. I have been in salons that take a deposit on appointments, but I know in my area that is not a common practice. Such an odd request would discourage many customers. If this is a customer that returns without an apology, explain your cancellation policy and if it continues you may have to require a non-refundable deposit.