The following plea for my advice was made on YouTube, on a page that shows my videos. I responded exactly as you see below but for some unknown reason YouTube wasn’t able to post my response, so I’m putting it here.
“I am currently in barber school. They don’t teach us much. They just through (sic) us out there and tell us that’s how we will learn. I am very nervous when a client walks into the school for a hair cut. I really don’t where to start on a hair cut. Any advice?”
There are three basic options for that client of yours, so to find out which option they want, begin by asking how they like their hair cut. First, you may find they want a “trim” which is basically the same haircut they’ve had before, or the second option is they want some kind of haircut that’s quite different from what they’ve had before. The last option would be a request for a haircut that is known by a common name (a “crew-cut”, a “fade”, etc.).
Giving a trim is quite easy. Hair on the cranium grows at a fairly uniform rate all over, so you need to know how long it has been since their last haircut—hair grows about a half-inch a month (more or less a little), so if their last haircut was six weeks ago, you need to cut off 3/4 inch all over the sides, back and top—one month of growing would need a half-inch cut off, etc. Besides how long it has been since the last haircut, a question that helps to “zero-in” on your client’s preferred haircut is to ask about the side hair—do they want a medium cutting or light sides or a skin-tight cutting. Lastly, ask if they want the bottom neck hair tapered or blocked.
If your client wants something quite different from their last haircut, you need to know about several different hair qualities, and how they determine what can and can’t be done in terms of hair length and shaping possibilities. There’s not room in this forum to discuss this subject—my videos and book deals with this subject in detail. Other than spending time with my how-to, you’ll learn about this subject through trial and error.
To give someone a requested haircut by a common name means you have to get familiar with different haircut names and how they’re done. These haircuts will also need some questions like how long to leave the top, sides, sideburns, etc.