You've validated your idea. You know people want it. Now comes the moment where most founders make a critical mistake: they jump straight into code.
Here's what happens next: The developers build what they think you mean. You realize halfway through that the user flow is confusing. The database structure doesn't scale. The UI doesn't match user expectations. Three months later, you're rewriting everything because nobody took the time to think it through first.
Design isn't about making things pretty—it's about making decisions before they're expensive to change.
What You'll Learn
Design decisions made in code cost 10x more to change than decisions made in Figma.
User flows, interface mockups, and working with your technical partner—what you design and what they implement.
A practical framework: user flows first, wireframes next, mockups last, then handoff to your technical partner.
Designing too much, skipping user flows, ignoring mobile, and not involving your technical partner early.
The specific tools you need: Figma for mockups, FigJam for user flows, plus inspiration sources.
Reading time: 12 minutes | Time to design: 1 week
Why Design Prevents Expensive Rework
Changing a user flow in Figma takes 10 minutes. Changing that same flow in code—after it's been built, tested, and integrated with your database—takes days or weeks.
The cost multiplier is real:
- Change in design: 30 minutes, $0 if you're doing it yourself
- Change in development: 2-5 days, $2,000-$5,000 in developer time
- Change after launch: 1-2 weeks, $10,000+ (includes bug fixes, testing, redeployment)
Design is where you make mistakes cheaply. Code is where you make them expensively. Production is where they become disasters.
But here's the trap: most founders either skip design entirely (and pay for it in rewrites) or over-design (and never ship). The MVP design sweet spot is designing just enough to avoid expensive mistakes, but not so much that you're planning features you'll never build.
The Three Layers of MVP Design
MVP design has three layers. Most founders do layer 2 (UI mockups) and skip the other two. That's backwards.
Layer 1: User Experience (User Flows)
What it is: A visual map of how users move through your product to accomplish their goals.
Why it matters: You can have a beautiful UI with a confusing flow. Users click around, get lost, give up. User flows force you to think through the journey before you design a single button.
What to create:
- 3-5 core user flows (signup, main task, payment, etc.)
- Happy path + 1-2 error states per flow
- Decision points (what happens when X?)
Time investment: 1-2 days
Tools: FigJam, Miro, or even pen and paper
Layer 2: User Interface (Wireframes & Mockups)
What it is: Visual representations of what users see and interact with.
Why it matters: This is where you catch UI problems. Is the call-to-action obvious? Do users understand what to click? Is the information hierarchy clear?
What to create:
- Low-fidelity wireframes for all core screens (grayscale, boxes and text)
- High-fidelity mockups for 3-5 key screens (with real colors, fonts, branding)
- Mobile versions of your 3 most important screens
What to skip: Don't design every edge case screen. Don't create 47 color variations. Don't design features you haven't validated.
Time investment: 3-5 days
Tools: Figma (industry standard), Sketch (Mac only), or Penpot (free, open source)
Layer 3: Working with Your Technical Partner
What it is: Once you've designed the user experience and interface, your technical partner handles the implementation details—database structure, APIs, hosting, and technology choices.
Your job as the non-technical founder:
- Define what success looks like: "Users should be able to complete signup in under 2 minutes"
- Specify the features: "We need login, password reset, and Google sign-in"
- Prioritize: "Authentication is must-have, social login is nice-to-have"
- Understand trade-offs: "If we skip feature X, can we launch 2 weeks earlier?"
Their job as the technical partner:
- Choose the database, hosting, and technology stack
- Design how data is stored and retrieved
- Integrate third-party services (Stripe, Auth0, SendGrid)
- Make decisions about performance, security, and scalability
You design the experience. Your technical partner designs the system. Don't try to do their job—trust their expertise on implementation.
How to communicate: Instead of "We need a relational database with normalized schema," say "Users need to edit their profile information and we need to keep a history of changes." Your technical partner will translate that into the right technical solution.
The 1-Week Design Sprint: A Practical Framework
Here's the order that works. Don't skip steps. Don't do them in parallel.
Days 1-2: User Flows
Goal: Map out how users accomplish their core tasks
Process:
- List your 3-5 core user tasks (e.g., "New user signs up and creates first project")
- For each task, draw the flow: Entry point → Steps → End state
- Add decision points: "What if user enters invalid email?" "What if payment fails?"
- Review with someone who wasn't involved—can they follow the logic?
Deliverable: 3-5 user flow diagrams that show every major path through your product
Days 3-5: Wireframes
Goal: Design the structure and layout of your screens (no colors, no real content yet)
Process:
- Start with your most important screen (usually the main task screen)
- Use boxes and labels—this is deliberately ugly
- Focus on information hierarchy: What's the most important thing on this screen?
- Create wireframes for every screen in your user flows
- Get feedback from 2-3 people: Can they understand what each screen does?
Deliverable: 8-15 low-fidelity wireframes (grayscale, boxes, labels)
Days 6-7: High-Fidelity Mockups
Goal: Make 3-5 key screens look real (colors, fonts, branding, real content)
Process:
- Pick your 3-5 most important screens
- Add your brand colors, choose fonts, add real (or realistic) content
- Design mobile versions of your top 3 screens
- Add interactive prototyping: link screens together so you can click through the flow
- Test with 3-5 users: Give them a task and watch them try to complete it
Deliverable: 3-5 pixel-perfect mockups + clickable prototype
Handoff to Your Technical Partner
Once you've completed the design work, sit down with your technical partner (co-founder or fractional CTO) and walk through:
- User flows: Explain the logic and decision points
- Mockups: Show the clickable prototype and explain the interactions
- Priorities: Which features are must-have for launch vs nice-to-have
- Questions: Let them ask about edge cases, technical constraints, or alternative approaches
They'll translate your user experience design into technical architecture—database structure, APIs, technology choices, and third-party integrations. That's their expertise. Your job is to communicate the what and why. Their job is to figure out the how.
Four Design Mistakes That Sink MVPs
Mistake #1: Designing Too Much
You design 40 screens. You create a 60-page design system. You specify every animation and micro-interaction.
The problem: You're designing features you haven't validated. You're spending weeks on design when you should be testing with real users. The MVP design rule: If it's not in your first release, don't design it.
Mistake #2: Skipping User Flows
You jump straight to pretty mockups. Your screens look great individually, but the flow between them is confusing.
The problem: Beautiful screens with broken logic. Users get lost, abandon tasks, and leave. Always design the flow before the screens.
Mistake #3: Ignoring Mobile
You design for desktop. You assume mobile "will just work."
The problem: 60-70% of web traffic is mobile. If your product is unusable on mobile, you've lost most of your potential users. Design mobile-first, or at minimum, design mobile versions of your core screens.
Mistake #4: Not Involving Your Technical Partner Early
You design everything alone, then hand mockups to your developer and say "build this." They point out that half your designs are technically impossible or would take 6 months to build.
The problem: Involving your technical partner during design (not after) helps you catch problems early. They can say "this flow won't scale" or "here's a simpler approach" before you've committed to a design. Collaborate, don't dictate.
Your Design Toolkit: What You Actually Need
You don't need expensive tools. You need the right tools.
For User Flows
- FigJam (free) - Collaborative whiteboard, great for flows
- Miro (free tier) - Similar to FigJam, more templates
- Pen and paper (free) - Seriously, this works
For UI Design
- Figma (free tier) - Industry standard, collaborative, browser-based
- Penpot (free, open source) - Figma alternative if you want full control
- Sketch ($99/year, Mac only) - Still popular, but Figma is overtaking it
For Design Inspiration (When You're Stuck)
- Dribbble - UI design showcase
- Mobbin - Real mobile app screens
- Land-book - Landing page designs
Total cost if you use free tiers: $0. You can design an entire MVP without spending a dollar on tools.
How to Know When You're Done Designing
You're done when you can answer "yes" to these questions:
- Can someone unfamiliar with your product follow your user flows? If you have to explain what happens at each step, the flow isn't clear enough.
- Have you designed all screens mentioned in your user flows? If your flows reference screens you haven't designed, you're not done.
- Can your technical partner look at your mockups and understand what to build? If they're asking "what happens when X?" constantly, you haven't designed enough detail.
- Have you reviewed designs with your technical partner? They should have flagged technical constraints or suggested simpler approaches before you finalize.
- Does someone who isn't you understand your designs? Test with 2-3 people. If they're confused, fix it before you build.
If you can say yes to all of these, hand off to your technical partner for the Build phase. If not, spend another 1-2 days clarifying what's unclear.
Design enough to prevent expensive mistakes. Don't design so much that you never ship.
Final Thoughts
Design is not about making things pretty. It's about making decisions before they're expensive. It's about thinking through the user experience before someone writes code. It's about creating a clear blueprint that your technical partner can build from.
Spend 1 week designing the user experience. Save 1-2 months of rework. The math is obvious. The discipline is hard. But if you've validated that people want your idea, you owe it to yourself to design it properly before your technical partner starts building.
Next in this series: Build - how your technical partner ships your MVP in 6-8 weeks without sacrificing quality.
Disagree With My Design Approach?
Found a better way to structure user flows? Have a design horror story I should include? I'm always refining this based on real-world feedback.
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