Entrepreneurs have a secret weapon that anyone can invest in to get ahead. For me, it costs $400 a month.

Entrepreneurs have a secret weapon that anyone can invest in to get ahead. For me, it costs $400 a month. Rafael Nadal and his uncle, Toni Nadal, who coached him for most of his career. Julian Finney/Getty Images Bill Gates famously said, "Everyone needs a coach. … We all need people that give us feedback. That's how we improve."The best athletes have coaches in their corner. Influential business leaders and CEOs have advisors in theirs.No matter how talented, successful, or wealthy someone is, they're rarely doing it entirely alone. And coaching isn't reserved for people at the top. I hired a life coach at 31. I pay him $400 a month, and it's some of the best money I spend. I wrote about why here.Many business owners have told me something similar about the mentors, coaches, and classes they invest in: Bet on yourself, they say. It can pay off.Kyle Ray, who grew a window-cleaning side hustle into a six-figure business operating in multiple Texas cities, compares the right coach to a cheat code that can help you "collapse time.""When there's something I don't know or need to learn, I start to look for coaches or somebody who can help me speed up through time," he told me.Ray has worked with multiple coaches, joined mastermind programs, and taken classes on everything from using AI to training door-to-door salespeople.At this stage of his career, he said he's willing to pay for knowledge that can speed up his development: "It's like, I need to learn this skill. I need to find out who's doing it better than I am, who can teach me, and what it costs. And then I'm just going to pay for it so I can learn."If hiring a coach isn't in your budget, start with a mentor. Find someone who is already doing what you want to do — and doing it well — and ask whether they'd be willing to share some advice. That's how Ray got started when he was strapped for cash. He bartended and waited tables to pay the bills while gradually building Geek Window Cleaning. It took about seven years before he was earning enough from the side hustle to leave his service jobs."I just found somebody who was doing better than me," he said. "I asked: What are you doing that I'm not doing? And what do you see that I'm doing that's preventing me from breaking through to the next thing?"Stavya Nilawar, a 19-year-old college student running a creator-marketing agency from his dorm room, took a similar approach."I would reach out to agency owners who were in the position that I wanted to be in," he told me. "I literally asked them what they're doing now in their day-to-day business and how they got to the next level."Nilawar recommends that early-stage founders do the same: Look for someone running a similar business at a more advanced stage, then reach out. Those conversations can offer guidance now, and potentially lead to collaborations down the line.There are other accessible ways to invest in yourself, too: Attend a conference, join a mastermind group, enroll in a class, or pick up a leadership book.Before Ray had money to invest in coaches, he read to get ahead. He credits much of his business's success to principles he picked up from business and leadership books. His top recommendations include "Drive" by Daniel Pink, "Dare to Lead" by Brené Brown, and "Beyond the Hammer" by Brian Gottlieb.As for networking events, I've been in rooms with top Amazon sellers and real-estate mavens. Each time I've attended a conference for reporting purposes, I've come away with the same realization: I'm missing out by not getting out more. Read next Business Insider tells the innovative stories you want to know Business Insider tells the innovative stories you want to know Business Insider tells the innovative stories you want to know Business Insider tells the innovative stories you want to know Business Success