How to Start a Business: A 90-Day Guide for Founders

Your First 90 Days: A Tactical Playbook for Launching Lean

Every founder wants to build something that matters. But the path from idea to viable business is a minefield of early decisions that can kill your company before it takes a single step. This isn't another generic guide. This is your tactical manifesto for the first 90 days, built on one principle: ruthless efficiency.

Forget vague advice. You need concrete steps, dollar figures, and frameworks. This playbook organizes your launch into five clear phases, designed to get you from a raw idea to a fundable entity in one business quarter.

Step 1 (Days 1-30): From Idea to Validated Problem

Your idea is a hypothesis, and it's probably wrong. The single biggest mistake founders make is building a solution for a problem that doesn't exist, isn't urgent, or that no one will pay to solve. Your only job in the first 30 days is to validate the problem .

Action: Conduct 50+ Customer Discovery Interviews

This is non-negotiable. Don't talk to your friends and family; they will lie to protect your feelings. You need to talk to strangers who represent your ideal customer profile.

LinkedIn Sales Navigator: Search for your target persona by title, company, or industry. A 1-month subscription is worth the investment. · Niche Communities: Find the Reddit, Discord, or Facebook groups where your target users complain and ask for help. · Cold Email: Use tools to find email addresses and send a simple, honest outreach message.

Hi [Name], I'm doing some research on how [role, e.g., 'e-commerce marketers'] handle [problem, e.g., 'shopping cart abandonment']. I'm not selling anything. I'm just trying to understand the challenges in your workflow. Would you be open to a 15-minute chat next week to share your experience?

Asking the Right Questions

Your goal is to get them talking, not to pitch your idea. Avoid leading questions. Focus on past behavior, not future promises.

Bad: "Would you use an app that automatically recovered abandoned carts?" (Future hypothetical) · Good: "Walk me through the last time you dealt with an abandoned cart. What did you do?" (Past behavior)

Bad: "Don't you think it's a pain to manage this manually?" (Leading question) · Good: "What are the biggest frustrations with how you handle this now?" (Open-ended)

Bad: "How much would you pay for a solution?" (Abstract) · Good: "How much does this problem cost you per month, in time or lost revenue? What tools are you paying for now to try and solve this?" (Quantifies pain & existing budget)

You're listening for "hair-on-fire" problems. These are issues so urgent people have already cobbled together a solution (even if it's a messy spreadsheet) or have a dedicated budget line item to address it.

Step 2 (Days 31-60): Build a Smoke Test & Generate a Waitlist

Once you've validated the problem, you need to validate that your type of solution is desirable. You do this not by building a product, but by building a "smoke test"—a landing page that sells the vision before it exists.

Action: Create a One-Page "Coming Soon" Site

Your goal is to build this in a weekend for less than $100. Use tools like Carrd, Leadpages, or Webflow.

The Problem-Promise Headline: State the problem and promise the outcome. Example: "Stop losing sales to abandoned carts. Our tool recovers 80% of them automatically." · Three Bullet Points on Benefits: How does it work at a high level? Focus on the "what," not the "how." · A Mockup/Visual: A simple Figma or Canva design showing what the product could look like is enough. It just needs to make the idea concrete. · A Single Call-to-Action (CTA): An email field with a button that says "Request Early Access" or "Join the Private Beta."

Now, go back to the communities and people you interviewed. Say, "Thanks for your feedback. We're building this based on our conversations. Here's the page if you'd like to get on the waitlist." Your goal is to get your first 100 waitlist signups. This is the first tangible asset of your company: a list of qualified, interested potential buyers.

Step 3 (Days 61-75): The Boring (But Critical) Legal & Financial Setup

With validation in hand, it's time to build the corporate container for your company. Getting this wrong creates expensive messes that can kill deals later.

Action: Incorporate as a Delaware C-Corp & Open a Bank Account

Why a Delaware C-Corp? Because it's the required structure for virtually all venture capital investors. It allows for different classes of stock (common for founders/employees, preferred for investors) and is legally well-understood. Do not form an LLC if you ever plan to raise money. · How to do it: Use a service. Stripe Atlas or Clerky are the standards for tech startups. They handle the filings, provide standard legal documents, and can cost as little as $500. This is not the place to get creative to save a few bucks. · Open a Business Bank Account: As soon as you have your EIN (tax identification number), open a dedicated bank account. Services like Mercury and Brex are built for startups. Never use your personal bank account for company expenses. Co-mingling funds is a nightmare for accounting and a massive red flag for investors.

Step 4 (Days 76-85): Founder Equity & Your 409A Valuation

You and your co-founders need to formally own the company you just created. Simply agreeing "we're 50/50 partners" means nothing legally.

Action: Paper Your Founder Stock and Get a 409A Valuation

Issue Founder Stock: Using the templates from your incorporation service (like Clerky), formally issue shares to all founders. These shares should be subject to vesting. · Standard Vesting Terms: The non-negotiable standard is a 4-year vesting schedule with a 1-year "cliff." This means you don't get any stock until your 1-year anniversary, at which point you get 25%. The rest vests monthly for the next three years. This protects the company if a founder leaves early. · Get a 409A Valuation: Before you can even think about hiring your first employee and offering them stock options, you need an independent 409A valuation. This is an appraisal of the fair market value (FMV) of your company's common stock. The strike price for all options must be at or above this FMV. Getting this wrong can result in huge tax penalties for you and your employees. Your law firm or services like Carta can arrange this, typically for $1,000-$2,000.

Common Mistake: Promising equity in an email or conversation. Equity promises are only real when they are documented and approved by the board of directors. Informal promises are a recipe for lawsuits.

Step 5 (Days 86-90): The Pre-Fundraising Checklist

You're not ready to raise a full seed round yet, but you are ready to start building relationships with advisors and potential angel investors. Before you send a single email, audit your progress.

The 90-Day Audit Checklist

[ ] Problem validated via 50+ customer interviews. · [ ] One-page business plan/lean canvas is complete. · [ ] Smoke-test landing page is live. · [ ] Waitlist has 100+ qualified signups. · [ ] Delaware C-Corp is formed. · [ ] Business bank account is open and funded with a small founder contribution. · [ ] Founder shares are issued and subject to vesting. · [ ] 409A valuation is complete.

If you have checked all these boxes, you have had an incredibly productive 90 days. You are now more prepared than 99% of first-time founders.

Subject: Quick Update: [Your Company Name] - Validated Problem & 100+ Waitlist

Hi [Name], Hope you're well. Following our chat, I spent the last 90 days focused on validating the problem around [problem area]. Wanted to share a quick update on our progress:

Spoke with 50+ [target customer persona] and confirmed their #1 pain point is X. · Built a simple landing page to test the solution, and we now have over 100 people on the waitlist. · Incorporated as a DE C-Corp and handled all the initial legal/equity setup.

My goal wasn't to build a product, but to prove we had a real business first. Based on this traction, we'll start building the MVP next month. No "ask" here, just wanted to keep you in the loop. If you have 20 minutes in the coming weeks for a more detailed chat, let me know.

This email shows progress, rigor, and respect for their time. It makes them want to take a meeting with you.

How to Apply This This Week

Identify 10 potential customers on LinkedIn. Don't contact them yet. Just build the list. · Write your "bad questions" and "good questions" list. Tape it to your monitor. · Draft your cold outreach email. Get it ready to send. · Sign up for a Carrd or Leadpages account. Get familiar with the tool before you need it. · Read about the 1-year cliff. Understand why it's a founder's best friend.

The journey of a thousand miles begins with a single, well-executed step. This playbook is your map for the first leg of the race. Now, get to work.