Keep pulling the thread on Y Combinator.
According to a survey of Y Combinator founders, a startup's first two to three customers almost always come from the founders' personal network, such as friends, former colleagues, or classmates.
Among Y Combinator founders surveyed, Apollo was the most commonly used tool for initial lead generation.
Based on a survey of Y Combinator founders, acquiring customers 4 through 10 typically requires unscalable methods like in-person meetings, direct messages on Reddit, and small, personalized events.
According to Y Combinator's observations, high-volume outreach tools like Apollo and Clay become effective for startups only after they have acquired their first 10 to 50 customers and refined their value proposition.