How should I approach formulation as a beginner?
Short answer
Learn the protocol, then learn what each ingredient does and why it goes in at a particular phase and temperature, before you start changing recipes.
Explanation
The skincare book is built around understanding. Every formula lists each ingredient's INCI name and function, groups ingredients into phases, and gives target temperatures, a target pH, shelf life and a 'key improvements' note that explains the formulation choices.
Four foundations run through every product: hygiene (sterilized tools, a disinfected workspace), preservation (anything with water needs a broad-spectrum preservative), pH (matching skin's acid mantle, around 4.5–5.5) and patch testing. The first formula, a chamomile foam cleanser, is mixed without heat or emulsifying, which makes it an approachable first project.
What to do
- Make a formula exactly as written before adjusting it.
- For each ingredient, ask what it does and why it goes in at that phase.
- Record temperature, pH and results for every batch.
Source: The Big Book of Homemade Skin Care — The Non-Negotiable Protocol · Calming Chamomile Foam Cleanser