A Practical Preservation Masterclass for safe, stable DIY skincare
Learn how to select the right preservative for any formulation in just 120 minutes
Does this sound like you?
You want to make safe, stable skincare—but your preservative research turns up contradictory information, leaving you more confused than ever.
You don’t know why you’d choose one preservative over another & have no idea how to tell if your preservative is actually working.
When a formulation uses a preservative you don’t have, you’re not sure what you can safely use instead.
If a DIY grows mould, you’re not sure why (or how to stop it happening again).
I get it!
Preservation felt scary and confusing until I learned this.
You ask a simple question—“What preservative should I use?”—and get a dozen conflicting answers, all confidently delivered as the truth.
Some say use Optiphen Plus. Others insist only Liquid Germall Plus will work. Someone else chimes in that Euxyl k 712 is the obvious choice, though it only works with “boosters” (what are those?!).
It’s overwhelming and stressful; getting it wrong means spoiled products, skin irritation, or worse.
So which preservative should you actually use? It depends.
But if you don’t know what “it” depends on, you’re stuck guessing, worrying, and hoping.
That’s why I built The Practical Preservation Masterclass.
You’ll learn what “it” depends on, what to buy and use, how to know if your preservative is working, and more.
This masterclass is built on over a decade of experimentation, research, and failure-so-you-don’t-have-to. It’s the guide I wish I had when I started.
Because once you understand what actually matters, preservation stops feeling confusing, limiting, and scary—and you can create the skincare you want to make, with ingredients you’re excited about.
What people are saying about my workshops & classes…
I highly recommend this course
I am enjoying this. I am not just learning, but understanding better, what goes into formulating.
– Kimberly Gardner
That was FUN!!
Oh my goodness, I learned a lot and am excited to experiment and gain a deeper understanding of how various ingredients influence the final product. This is so much fun.
The course was wonderfully paced, informative, funny, and I’m ever so grateful to have such an amazing teacher.
Highly recommend!!!
– Sherry McCauley
love love love everything about this!!!
– Marguerite Love
I am loving every minute of this course!
Timely information that is not hard to understand and certainly not overwhelming.
Marie makes everything very understandable. From baby step walking us through to all the wonderful videos showing the procedures, how can you not love this!
– Teresa Schwenk
Confidence Booster Achieved
This course single-handedly gave me so much more confidence in my ability… I feel like I am actually “graduating” in my understanding!
Did NOT know that I would come to learn this much!!! Mahalo Marie for all of the tireless work you invest to help those of us who tire of not having exactly what we want in our skincare, and settling for what is sold.
– Ku’ulani Koenig Armistead
Engaging and informative
Marie has a light hearted nature and a clear passion for what she is teaching, making each lesson not only educational but enjoyable.
She is very thorough at explaining not just how to make a product, but why you use each ingredient; how they work together; and often with suggestions on how to experiment with it on your own. These experiments will help you to more deeply understand her teachings as well as learn how to alter the formulations to your liking.
I wish this course would have been around when I was just starting out, it’s a very valuable resource for beginners and I highly recommend it!
– Carli Cook
Love the format and the depth of information
I have been DIYing with Marie for just over a year. I have all of her workshops… I love the format and the depth of information she provides in each of them. I regularly go back and re-watch.
– Apple User
In The Practical Preservation Masterclass you will learn:
How to choose preservatives for your formulations with confidence (and know when not to use one)
Instantly know if a formula will be easy or hard to preserve—and make any formulation easier to preserve without sacrificing the ingredients you’re excited about
Take charge: Understand the science behind spoilage so it’s no longer a scary mystery.
Which preservative(s) to buy based on your experience level + formulation priorities
Make sense of conflicting advice by learning what those “it depends” things actually depend on
Set your DIYs up for success—even if you’re using hard-to-preserve ingredients
Understand how big companies ensure their preservatives work so they don’t get sued—and how you can steal those strategies for use at home
Stop letting fears about safety and preservation limit what you make
Learn how to avoid disasters like this
And make beautiful, safe formulations like this
FREE BONUS
Make Smarter Preservation Choices Faster
Receive a free copy of my never-before-shared 20+ page Practical Preservation PDF Cheat Sheet!
It includes over a decade of preservation know-how, including:
- How to use any preservative: what you need to know, why it matters, and where to find the information you need
- My step-by-step guide to choosing a preservative for any formula
- The formulation & process I use to test all new-to-me preservatives
- Must-have ingredient and equipment lists
- PLUS: Detailed, printable profiles for the twelve most common DIY preservatives
Stop guessing, Googling, or hoping your go-to preservative is enough.
Learn how to actually work with preservatives—not just follow rules you don’t understand.
Everything you’ll receive:
A ticket to the live masterclass and Q&A (+ lifetime access to the replay)
Join me live on February 8, 2026 for the full presentation and ask your questions afterwards in the live Q&A
Preservative insights & experimentation guidelines
You won’t just follow recipes—you’ll learn the “whys” behind each project so you can understand how it works and begin to create your own formulations!
Tried & tested formulation strategies
Learn the exact techniques big brands use to create safe, microbe-free formulations—no more guessing about what works!
The ultimate preservation cheat sheet
A quick-reference printable guide that’s packed with preservation insights to make preservative selection & formulating faster and easier.
The "whys" behind the rules
Stop blindly following rules you’ve seen online and start actually understanding.
7-day Money back guarantee
I’ve spent years developing the framework & understanding I teach in The Practical Preservation Masterclass. It contains everything I wish I’d known as a newer maker so I didn’t spend years worried about mould & fretting over the conflicting advice I found in Facebook groups.
If you go through the masterclass and still can’t choose & support preservatives for your formulations, send me an email within 7 days and I’ll refund your money.
Who is this not for?
Those looking for a “one & done”, “guaranteed to work every single time for exactly this long” answer (because this doesn’t exist!)
Makers looking for an exhaustive course on all things microbial/spoilage/microbiology; this masterclass is about practical, hands-on knowledge
Who is this for?
Makers who want to understand the WHYs behind preservation—not just be told what to do
People who are excited to experiment and learn hands-on
Those who have a decent selection of ingredients and equipment OR are willing to invest at least $200USD to get started
Stop worrying about safety. Create products you love.
You can formulate anything with confidence once you understand what actually matters in the battle against dangerous microbes that ruin skincare.
FAQ
Does this masterclass include tutoring/on-going support?
No, The Practical Preservation Masterclass does not include ongoing support.
If you need additional support I recommend becoming a Humblebee & Me patron at the “Tier 3: Royal Jelly” level; this includes two live ‘office hours’ sessions each month where you are welcome to ask questions.
How do I access the masterclass?
Simply log in to the Workshops portal, select The Practical Preservation Masterclass, and voila!
How long will I have access to the masterclass?
Your access does not expire! You’ll have as long as you need to work through the materials and can revisit it whenever you like.
Are the preservatives discussed natural?
Some are, some aren’t. You’ll learn many strategies to help you formulate safe & stable natural cosmetics if that is your goal.
Will this masterclass teach me how to make products with guaranteed shelf lives?
Preservation is a huge topic full of endless variables, so there’s no way to make huge promises like this. That would be like taking a cooking class expecting to learn how to develop recipes that taste amazing every single time without ever needing to taste the food!
You will learn strategies to improve the chances of success of your preservation system, but as with cooking, the only way to know for certain it works is to test it and see.
I will share my experiences and great starting points if you aren’t interested in doing lots of your own testing, but because there are so many variables when it comes to making DIY skincare, there’s no way for anyone to promise anything will work for X amount of time in every single product.
Do the videos have subtitles?
The replay will have full English subtitles, but the live presentation will not be captioned.
All written materials are in English.
Can I get a refund?
I’m thrilled that you’re considering signing up for my masterclass, and I want you to sign up with complete confidence. That’s why I offer a 7-day money-back guarantee.
I’m super confident this masterclass will leave you feeling more confident when it comes to working with preservatives: you’ll understand the main types you’re likely to encounter (including their strengths and weaknesses), know how to make your formulations easier to preserve, and know how to test your preservatives to gain confidence in their performance.
This masterclass is not a single one-size-fits-all, “works every time without testing” answer because that doesn’t exist. It’s about understanding what really matters in the battle against microbes so you can choose and use preservatives that fit your formulation values & goals. If that’s not what you’re looking for, this masterclass isn’t for you.
So, if you buy this masterclass, watch the entire presentation, read all the materials, and still don’t understand how to choose, use, and test preservatives in your formulations, send me an email within 7 days and I’ll refund your money.