One of 3 ways usually.
1) Start a business that ends up being a successfull business and it doesn't fail. Many businesses fail.
2) Be a really successfull investor, and over many years you can make alot of money. It takes alot of work.
3) Graduate college, get a job and work your way up in the company over the years.
The key thing in all these is it takes alot of hard work and making smart decisions.
A lot of it IS luck. People ahead of you retire or relocate, and you are the best qualified one to take their slot. You work for a company that is bought out, and all your stock options vest. You work for a small or medium sized company, and it "blows up." I've seen all of these happen.
Save and invest, compunding principle
Easy, just don't live in the U.S.
Steal money, speak lie, and so on...