Buy or develop your own time machine and go back to 2008 and mine BTC on the computer at your mothers house in the basement
If you want to become rich then you will need to work hard and only focus on working and working that is how you become successful.
People who are rich these days all worked hard and did not think about the money.
Yeah there is no substitute to get rich, if you want to get rich then you definitely need to work hard in achieving your targets and if you successfully do it then you can become rich in future.