The best I ever received? Start saving and investing when you’re young to benefit from compound interest over time. I didn’t take the advice, but I received it!
If you worked for $8/hr and took 5% of your income and put it towards retirement (I know 5% is a lot when you're broke) from age 18-67 assuming you got a 2% raise every year, you could retire with ~$385,000 in the bank and it would last you until you were 79. That's using the default numbers from Bankrate. If you could bump your savings rate up to 15% using those same numbers (which is admittedly unrealistic) you would be a millionaire at retirement. The moral of the story is start early and be consistent.
If you're making $8/hr, your head is going to be incredibly deep underwater. 5% is not remotely possible at that wage. At 15% you may as well be living in fantasyland.
Most people wouldn't remain at $8/hr their whole life, you would likely earn more as you gained training and experience. My point was that at the extreme low of full time wages, your savings rate at an early age helps determine where you would end up. It's doable especially at hire wages.
When I was making that kind of money, I still saved way more than 5%. Granted, after inflation, it is like $11.50 now. Still, 10% would have been pretty easy. 20% would be possible if I didn't blow money on things like spend $3K on a bike for hobby use. Also, that's assuming you don't have unexpected expenses. I lived somewhere where having a car wasn't necessary, so that made a huge different in budgeting. And when I needed surgery, I was lucky with insurance. Otherwise, that could have easily have eaten up the savings I had.
So 15% is definitely possible... with lots of luck and good circumstances.
The fucked up thing about plain money is that even if you have a million today, that million will be worth less than half when you retire, due to inflation and nrtions that keep printing more money to cover their expenses.
People with money usually don't keep it as plain money though. On average, if you just invest it in S&P500 (assuming historical returns), it'll be worth at least 4 million after adjusting for inflation after 30 years. 3 million dollars reward for having 1 million dollars. But even if you're like a gold-standard fanatic and just put it in gold, the same applies.
Saving and investing is also way easier if you don't give yourself the option to not do it. You won't manually move 10% of your money each month, but if it goes to a 401k or a separate account automatically it's far more likely to stay there.