A silly thought experiment
For 2 decades, Amazon had essentially zero profit. They plowed every last cent of revenue into growing even more revenue.
Amazon is the largest Internet-based retailer in the world. And they keep expanding in all directions, no matter how tangential to internet retail. Semi-trucks barrelling down the highway with Petabytes of data? Original TV series? Grocery stores with no check-out lines? Flying delivery drones? All Amazon.
What if you operated like Amazon? Took all of your spare cash and invest it in your own personal infrastructure? Can you make every dollar that comes through your checking account work to accelerate your earning potential? 
Sound too risky?
You've probably already done something riskier.
If you took out a student loan for college, you took on debt to improve your future revenues.
Why did you stop investing in yourself after college?
The standard advice is to save 10% for retirement. FI/RE people say save 50% into stocks, or maybe real-estate. Stocks might get you 7% returns over time, which is pretty damn good.
You can do better than 7%. 
Books are cheap and well worth the investment. You get years of someone's life and research and thoughts distilled into ~250 pages. If you gain one insight and take action on it, you've likely more than doubled your investment.
Everything else on this list could be learned from a book.
There's a subset of skills which are useful in every field. Spend money and time on a good course/teacher.
- Public speaking courses
- Writing courses
- Selling courses
- Coding courses
- Continuing Education courses
Get your mindset right and you'll go far. Learn to form habits, shut out distraction, do Deep Work, and do the gritty boring stuff even when you don't want to.
- Learn about psychology.
- Find a mentor and work for them pro bono.
- Therapy - if you have mental roadblocks, there's nothing wrong with getting help
- Hire an accountability coach
Get your biochemistry right and you'll have more capacity to take on hard challenges.
- Hire a nutritionist - figure out the foods that make you sick and the foods that make you tick.
- Hire a PT or commit to fitness classes - Like it or not, you have a physical body that was made to move. Move.
- Get Better Sleep - Turn off your screens an hour before bed and get some blackout curtains.
Start a side-hustle/freelance
Side-hustle can give you a reason to focus on learning new skills. And maybe you'll make some extra money.
At some point you'll become time-limited. Prioritize your life, then think about hiring help.
- Hire a chef or get food delivered
- Hire someone to clean
- Hire an assistant
Move to where the action is
Want to run a startup (or work at one)? Move to Silicon Valley. Want to be a movie star, or a screenwriter? Move to LA. Want to be in finance? Move to NYC. etc. You might have sticker shock at the rent, but you need to live where everything is happening.
Can you run your personal finances like Amazon? Where else can you invest your profits? Let me know.
 I am not a financial advisor. None of this is financial advice. I'm a random dude on the internet. Don't take financial advice from random people on the internet.
 Do you have credit card debt? Drop everything and fix that first.
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