Financial strategies I've learned over the years.

"Return On Result" is a more important concept than return on investment. ie, a stock portfolio that earns 10% may not be the right tool if the result you really want is income and peace of mind. Start with the end result you want, and calculate the return based on that result. The highest number isn't always the best one.

"Return On Investor" is not the same as "Return On Investment." Sometimes you need to think about your personal financial situation at the macro level. Someone who only saves 5% of their income and earns double digit returns will still end up with less than someone who saves 20% of their income in much safer, conservative, and therefore lower yielding investments.

Investing in your own earning power is often the best place to put your money (ESPECIALLY early in your career, when even small increases in income have time to compound over decades). The same logic is true of individuals and corporations: when you reinvest earnings back into growth--versus paying yourself a dividend--you are increasing future earnings. If you have $5,000 to invest in stocks, consider how you might instead invest that $5,000 in hiring a mentor, consultant, joining a mastermind, or learning a new skill. More than likely, investing $5,000 in your own education could create a new skill level that could earn you at least an additional $5,000 per year in income. That's a 100% return....every year.
To quote Warren Buffett, "Investing in yourself is the best thing you can do. Anything that improves your own talents; nobody can tax it or take it away from you. They can run up huge deficits and the dollar can become worth far less. You can have all kinds of things happen. But if you’ve got talent yourself, and you’ve maximized your talent, you’ve got a tremendous asset that can return ten-fold."

Peace of mind is very connected with liquidity. If the purpose of getting rich is to buy happiness, it makes no sense to stockpile money if it's stressing you out. Most people do not care about the liquidity of their investments; they should. Optimize for happiness, not net worth.

Opportunity is often the inverse of competition. Where there is less competition, there is more opportunity. Right now, the most popular "alternative" investments like real estate, crypto, etc are pretty crowded. One industry where there is extremely minimal competition is business itself. Millions of baby boomer business owners will be retiring soon, and would love to sell their book of business to young whipper snapper millennials. It's often safer to buy an existing business than start one from scratch. There is almost non-existent competition here, because most people are intimidated at the idea of buying a business. The cash on cash return is usually 10%-30% if you buy at the right price. And unlike stocks, you can personally improve your investment and increase its returns.

Finally, you cannot "save" your way to retirement. Inflation will murder your portfolio. Most people are only assuming 1% inflation, maybe 2%. In all likelihood, it will be far higher. Personally I use 3% when I modelled my plan. This absolutely devastates your assumptions about how much you need to be saving if you don't want to be eating Ramen in your golden years. Taxes will also be higher in the future, making it even harder to save in the first place.