skincare, one step per page
Twenty-four lessons on the routine your skin actually asks for: a cleanser, a moisturizer and a sunscreen as the whole core, thin-to-thick ordering, lukewarm water and the tight-feeling warning, what a moisturizer's three jobs really are, SPF as arithmetic with the two-finger and shot-glass measures, UVA versus UVB, the actives in plain words from retinoids to niacinamide, and the boundary where a dermatologist takes over.
One lesson, one diagram, and one thing to do this week. That's a page.
skincare, one step per page
Twenty-four lessons on the routine your skin actually asks for: a cleanser, a moisturizer and a sunscreen as the whole core, thin-to-thick ordering, lukewarm water and the tight-feeling warning, what a moisturizer's three jobs really are, SPF as arithmetic with the two-finger and shot-glass measures, UVA versus UVB, the actives in plain words from retinoids to niacinamide, and the boundary where a dermatologist takes over.
Set in Space Grotesk, Inter and JetBrains Mono (SIL Open Font License).
Every fact in this book is as the primary source states it, fetched and read during this build: the American Academy of Dermatology pages on how to apply sunscreen, sunscreen FAQs, common sunscreen mistakes, face washing 101 and retinoid or retinol, the NHS page on sunscreen and sun safety, the Skin Cancer Foundation pages on sunscreen and how to apply it, and the Wikipedia articles Sunscreen, Moisturizer, Exfoliation (cosmetology), Retinoid and Sunburn, all cached at build time and cited in each lesson's source line. Where sources differ (the AAD's 15 minutes before going out against the NHS's 30), each is stated as its source states it. This is a book of routine mechanics, not medicine: no product or brand recommendations, ingredient classes only. General information only, not professional advice; see a dermatologist for diagnosis or treatment, and anything that smells like a condition is a dermatologist's topic from the first day. An independent guide; not affiliated with or endorsed by the AAD, the NHS, the Skin Cancer Foundation or Wikipedia. No facts are sourced from Reddit, YouTube, forums or search engines.
Your purchase is for personal use only. You do not have redistribution rights: please do not share, resell, or republish this book or its pages.
© 2026 Steve Hodgkiss. All rights reserved. Personal use only; no redistribution rights.
Edition 1.0 · stevehodgkiss.net
Contents
This book's plan: the whole routine is three steps. Per the AAD face washing page: use 'a gentle, non-abrasive cleanser,' rinse, 'pat dry with a soft towel,' and 'apply moisturizer if your skin is dry or itchy.' Per the AAD page on how to apply sunscreen: 'Choose a sunscreen that has an SPF of 30 or higher, is water resistant, and provides broad-spectrum (UVA and UVB rays) coverage.'
Three steps is enough
A routine is not a pharmacy shelf. It is a cleanser, a moisturizer and a sunscreen, SPF 30 or higher: wash, seal, protect. Three products, three minutes, morning and night.
Everything beyond those three is an extra, optional in a way the core never is. The AAD's sunscreen bar is specific: broad spectrum, SPF 30 or higher, water resistant.
If strangers are crowding your sink, this page is permission to put them in a drawer.
Tonight, line up what you own against the three jobs, and move everything that fits none of them out of sight for now.
Per the AAD face washing page: 'Limit washing to twice a day and after sweating. Wash your face once in the morning and once at night, as well as after sweating heavily. Perspiration, especially when wearing a hat or helmet, irritates the skin. Wash your skin as soon as possible after sweating.'
How often to wash
Twice is the number: once in the morning, once at night, plus one unscheduled wash. The AAD adds a condition people forget: after sweating heavily, as soon as possible, because sweat, especially under a hat or helmet, irritates skin.
More than that is not cleaner. The AAD's own washing steps are gentle ones, fingertips only, lukewarm water, no scrubbing.
Two scheduled washes, one after real sweat. That is the whole calendar.
Anchor the two washes to habits you already have, coffee and brushing your teeth, so the day does the remembering for you.
Per the Wikipedia article Moisturizer: occlusives 'form a hydrophobic coating on the surface of the skin, keeping moisture from escaping'; humectants 'are hydrophilic and absorb water' and 'can also draw moisture from deeper layers of the skin to the surface'; the word emollient 'is derived from the Latin verb mollire, to soften.' A layer of petrolatum on normal skin 'can reduce that loss by 50-75% for several hours.'
Three jobs, one cream
Three plain words run every jar on the shelf. A humectant holds water. An occlusive seals the surface so water cannot escape. An emollient softens; the word itself comes from the Latin to soften.
The numbers are real: a layer of petrolatum can cut water loss by 50 to 75 percent for several hours. That is what moisturized actually measures.
One caution from the same article: humectants alone can pull water up from deeper skin, so they belong with an occlusive, not instead of one.
Read your moisturizer's ingredient list once and mark which of the three jobs its first few ingredients are doing.
Per the AAD sunscreen FAQs: 'Dermatologists recommend using a sunscreen with an SPF of at least 30, which blocks 97% of the sun's UVB rays. Higher-number SPFs block slightly more of the sun's UVB rays, but no sunscreen can block 100% of the sun's UVB rays,' and high-number SPFs 'last the same amount of time as low-number SPFs.' Per the Wikipedia article Sunscreen, 'SPF 15' means that 1/15 of the burning radiation will reach the skin. Per the NHS sunscreen page, SPF is 'a measure of the amount of ultraviolet B radiation (UVB) protection.'
What SPF means
SPF is arithmetic. Per the Wikipedia article, SPF 15 means one fifteenth of the burning radiation reaches your skin; the AAD rounds it for SPF 30: it blocks 97 percent of UVB.
Check it yourself: 1 minus 1/30 is about 96.7 percent, the number behind the 97. The gap up to SPF 50 is a sliver, and no sunscreen blocks 100 percent.
The trap is time: higher numbers do not last longer. An SPF 50 that never gets reapplied is not outworking an SPF 30 that does.
Look at your sunscreen's number today and remind yourself what it buys: filtering power, not hours.
Per the AAD retinoid page: retinoids are 'a catch-all for an array of vitamin A-based products used on skin'; a board-certified dermatologist advises patients 'to use the least-intense retinoid formula they can find, and use it every other night to start, slowly building up,' because otherwise 'they end up irritating their skin'; because retinoids 'can make skin more sensitive to sun,' use it 'only at night' with sun protection by day; and 'Retinoids should not be used during pregnancy.'
Retinoids at night
A retinoid is a vitamin A based product for skin; the family name covers many strengths. The AAD's start is small on both axes: the least intense formula you can find, every other night, building slowly.
Skipping the slow start has a named consequence: you end up irritating your skin. Night is the slot because retinoids make skin more sensitive to sun; daytime answers with sunscreen.
Two hard notes: not during pregnancy, and anything prescription strength is a dermatologist's conversation.
If a retinoid is on your list, commit to the slow start before you buy anything: least intense formula, every other night, no exceptions.
Per the AAD face washing page: 'If you have questions or concerns about caring for your skin, you should make an appointment to see a board-certified dermatologist.' Per the AAD retinoid page: 'people who have moderate or severe acne scarring, or whose acne is associated with their menstrual periods or other hormonal changes... should really see a board-certified dermatologist before they try a retinoid,' and those with 'a lot of redness or inflammation in their skin' should 'ask their dermatologist.' Per the NHS sunscreen page, report 'any moles, freckles or patches of skin that change in size, shape or colour' to a doctor as soon as possible, because 'Skin cancer is much easier to treat if it's found early.'
See a dermatologist
A routine maintains skin; it does not treat it. The sources draw the line for you: questions or concerns about your skin warrant a dermatologist appointment, and hormonal or moderate to severe acne, scarring, or lasting redness are doctor topics from day one.
Some signals outrank the whole shelf: a new mole, or one changing size, shape or color, goes to the doctor as soon as possible, because skin cancer found early is far easier to treat.
The routine is the floor, not the ceiling. Know what it cannot do.
Learn the two lists this week: what a routine maintains, and what belongs to a dermatologist from the first day.