I used to cut by myself for several months when I first opened up my 1st shop. I had to learn to balance speed and quality. However, always choose quality over quantity. If you have several clients waiting and you know you won't be able to get to all of them in a sufficient amount of time; here is what i do....
I apologize to the clients for the wait, give them my business card ( if they are new), and let them know that I take walk-ins, but if they call for an appointment, they never have to wait. This is a great way to get a new client to return at a later date.