How should a person in their early 20s invest their money?

I would like to know the steps a person should follow to trade successfully in their early 20s.
1. Have a job that provides a decent income where you put 15% of each paycheck (after taxes) into an account that you don't touch. Transfer that from your checking account into the savings account the day you receive it. You'll never know the difference in how you live day to day.
2. Once that account reaches a certain dollar amount after a year or few, then look into establishing a trading account that you can fund with that money.
3. Make sure that you have at least 6 months of additional capital on the side that covers living expenses (and surprise expenses).
4. Set up and learn the ins and outs of a trading platform with a company that offers good executions and reasonable commissions.
5. BEFORE funding the account fully, paper trade.
6. And before paper trading, at least follow the markets you want to trade and establish a strategy or strategies that are profitable "on paper."
7. Lay out a plan of money management for each month/week/day for how much you are willing to lose on a percentage basis that will keep you in the game to learn while you lose.
8. Read trading psychology books so you don't become your own worst enemy.
9. When following your trading and money management rules on paper and show consistent profit, start trading real money using small share size.
10. Evaluate your trading at the end of every day and week to see where you departed from your plan ... and where your strengths are and where your weaknesses are.
11. CONSTANTLY reel yourself back in to stay true to your trading strategy/plan and money management plan.
12. Treat it as a long term business of accumulating versus trying to get "rich" overnight.
13. It's okay to not take trades and take a break from the markets ... feeling you must trade or you'll miss out is a recipe for disaster.
14. Once you've learned how to trade in real time and show profit, peel off a portion and tuck it away into your savings account.
15. Wash, rinse, repeat!
16. NEVER EVER exceed your loss/drawdown for a trade or a day (that you've specified in advance in your trading plan). If you do, you WILL FAIL and lose money!

I will surely follow these helpful steps. Thank you for the useful reply.