Your first head spa: what to expect From the curb to the blow-dry.

No. Turn up with your hair however it has been all day, or all weekend. The scalp camera reads an everyday scalp far better than a freshly washed one — oil around the follicle openings, product caught between the hairs, dry skin along the part — and a shampoo an hour beforehand takes away the thing your therapist is there to look at.

The cleansing is the job you are paying someone else to do. Every format but the 30-minute aromatherapy opens with a shampoo wash, and the 45-minute Classic runs it twice — more thorough than anything you manage standing up in a shower.

What if you have been using dry shampoo?

Say so, and come anyway. Dry shampoo leaves a fine residue that settles on the skin between the follicles, and it turns up on the monitor as a dull film most guests had no idea was there. It lifts out in the first of the two shampoos. There is nothing to tidy up before you arrive.

What if your color is only a few days old?

Book, and tell your therapist the date it went in so the products can be matched to it. Color that went in yesterday is the one case worth a call to the studio before you come. Where the color is part of a bigger project — bleach, highlights, daily heat — the 90-minute Luxury Milbon Restorative Head Spa at $150 is the format built for it, with hot steam and a Milbon treatment for hair that has been processed hard.

A digital scalp analysis, on a screen you can see from where you are sitting. A camera picks up one square of scalp and throws it up on the monitor, blown far past anything a bathroom mirror shows: the follicle openings, the oil around them, whatever has settled on the skin. Almost nobody has looked at their own scalp before.

Every head spa on the menu opens with it, from the $50 aromatherapy up to the $150 restorative, and what the screen shows decides which products come out of the cabinet. Oil pooling around the follicle openings and skin flaking along the part want opposite treatment, and hair type on its own is a poor guide to which of the two you have.

Ask your questions while the image is still up. That is the easiest moment in the whole appointment to change what gets used on you. The scalp analysis guide goes through what turns up on the screen and what it cannot tell you, and the full head spa guide lays out how the six stages fit together.

Anything you can lie down in for an hour. You keep your own clothes on, and your head goes back into the basin, so a stiff high collar is the one thing worth leaving at home. Big earrings come off before the massage starts — easier done at home than on the bed.

Do you have to make conversation?

No. Plenty of guests talk for the first few minutes, look at the monitor, and then go quiet. Falling asleep is ordinary. Say at the start if you would rather have a quiet room and that will be the end of it — nothing in the 45 or 60 minutes needs you to hold up your end of a conversation.

What about your phone?

You will not be using it. Your therapist's hands are on your scalp for most of the 45 or 60 minutes and your head is tipped back for the rest, so there is nowhere to prop a screen and no free hand to hold one.

See a dermatologist first if your hair is shedding in patches, if the skin is crusting, bleeding or sore, if flaking has outlasted the drugstore shampoo you tried on it, or if something has changed suddenly and you have no explanation for it. This is a beauty and relaxation service and it does not diagnose, treat or cure anything.

None of that rules out the appointment. See the doctor, get the diagnosis, then book — the two sit together well. What the camera puts on the monitor is a magnified picture of your skin, and your therapist will describe what is on the screen without putting a name to it.

Beyond that, a first visit asks nothing of you except unwashed hair and an hour you are willing to lose. Booking runs through Square, from 9 in the morning until 8 at night, any day of the week.