Business, Politics, & Society

How to Make a Prototype: Sara Blakely’s 7 Prototyping Tips

Written by MasterClass

Last updated: Nov 7, 2019 • 6 min read

For Sara Blakely it all started with a product idea. With no fashion background, no leadership experience, and no business degree, she set out to design an undergarment for women that would solve the age-old issue of underwear lines. The concept for Spanx was born, but before Sara could go into production for her new product, she had to start the way most businesses do: with a prototype.



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What Is Prototyping?

Prototyping is the design and fabrication of a mock-up of a product. It is an early essential phase of product development and the design process. The purpose of prototyping is to test the viability of a new design in its early stages, fix any design flaws, assess functionality, and get feedback from investors and potential users before sinking time and money into the mass production of the final product.

How Sara Blakely Created the Spanx Prototype

While hawking fax machines door-to-door in the Florida heat for the company Danka, 27-year-old Sara had to wear pantyhose (a dress code enforced by the company). While Sara liked the control-top element of the hose, she didn’t like the seam that showed through her open-toed shoes. She decided there must be a way to have one without the other.

Soon after, Sara had a chance to put the idea into practice. She had been invited to a party and decided to go in a pair of cream pants—a garment notorious for revealing underwear lines. To avoid any mishaps, she put on a pair of pantyhose, but first, she cut out the feet. Three years shy of her 30th birthday, Sara made the very first prototype for what was to become Spanx.

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Sara Blakely’s 6 Tips for Building a Prototype

Prototyping is a two-pronged process: First, it’s bringing your idea into the world to see if it can be made. Then, it’s examining the strengths and weaknesses of your product by comparing it to what else is out there.

1. Look to Other Products for Inspiration

It’s okay to Frankenstein parts of existing products together to create your first prototype: Steve Jobs didn’t invent the camera. Nor did he invent the phone or email. But he brought all of those things together in a single device. When Sara was prototyping, she borrowed ideas from different products, taking her fabric inspiration from one line of pantyhose and her waistband inspiration from another. When making your own prototype, don’t be afraid to gather intel on other products like yours to see what works and what doesn’t. Then, take what works and innovate on it.

2. Collect Feedback From Your Friends

Try your first few functional prototypes on yourself. If you wouldn’t buy it, and it was your idea in the first place, who would? If it passes the “would I buy it?” test, great—now step it up. Give your prototype to some trusted friends and family members to try. At this stage, you’ll be looking for constructive criticism about the real-world user experience. Vapid encouragement is nice when you’re feeling down, but when you’re trying to improve a prototype of your physical product, don’t welcome it. Ask your trusted testers the following:

  • What do you like about this product?
  • What are three things you would change about it? (Asking for three or more critiques will force testers to come up with real, useful suggestions—ask for only one and they might give you something lame, like, “It’s not exactly my size.”)
  • Would you use this?

Then, to push them to elaborate:

  • When would you use this?
  • Would you recommend it to a friend?
  • Could you see this being your first choice compared to similar products that exist on the market? Why?
  • Do you see a need for this?
  • What are my product’s three greatest flaws?

Testing out your working prototype on actual people is indispensable. When Sara learned that her manufacturer was sizing her product on plastic molds instead of real women, she decided to do something about it. Sara took her prototype to women she knew who wore the sizes small, medium, and large, and asked them to wear the prototype around. They made adjustments and comments: One woman ended up cutting the waistband. Another noted that the Spanx kept sliding down her legs. Their feedback was much more useful to Sara than a plastic mold could ever be.

3. Anticipate Objections

The thick fabric that Spanx products are made from could have been objectionable to some consumers who might view it as bulky or hot. But Sara anticipated her buyers’ objections and spun them into benefits: The thick fabric masks cellulite better and gives wearers a better silhouette. Figure out how to sell people on your prototype as you make it.

4. Keep Your Product’s Retail Price in Mind

If you’re making the rare product in an entirely new category, you may have more leeway to charge what you want, but odds are you’ll be facing established competition. You can start to determine a reasonable retail price for a product by looking at a typical example of the competition’s pricing. If you’re making something that’s similar to an existing product, you should have some semblance of a pricing roadmap that works. For example, if you’re making lipstick, you’ll know that a tube can command anywhere from single-digit prices for drugstore options to $38 for a shade by Chanel.

For Sara, footless pantyhose didn’t exist, but hosiery did, so she used that industry as a benchmark to price out her product. Spanx came out on the expensive end, but the idea was genuinely novel.

If you’re planning to sell your product wholesale—meaning you’re selling your products to a retailer that will then sell your products to their customers—remember this: In order to make enough money to stay afloat, your product will likely need to sell for at least five times more than the cost of making it.

5. Ask Yourself: Is Your Product Ready to Sell?

It took two years for Spanx to go from idea to marketplace. Of course, your timeline may be different depending on the product you’re creating. Spend as much time as you need in the prototyping process, perfecting your product before it goes public. It can be time-consuming, but it's worth it. Repeat the final assignment above again and again until your testers stop coming up with flaws.

You’ll know your product is ready to sell when:

  • It solves the problem you set out to solve.
  • It gives you the results that you’re looking for.
  • It differentiates itself from other similar products on the market.
  • It’s the best option out there.

6. Never Stop Iterating

One of the most important lessons in maintaining a successful business is to never stop thinking about your customers.

An entrepreneur’s job is to solve problems by making things better and easier for people. The world is always changing, so solutions can’t remain static. Think of how often Apple comes out with new iPhones. Sure, they’re creating a somewhat artificial need to upgrade, but at the same time, people are beginning to expect new and better technology.


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Learn More About Entrepreneurship

Sara Blakely had no fashion, retail, or business leadership experience when she invented Spanx in the late 1990s. All she had was $5,000 and an idea. Which means you can start your own billion-dollar business, too. Learn more about finding your purpose, making prototypes, building awareness, and selling your product in Sara Blakely’s MasterClass.

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