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Many employers offer the opportunity to automatically put aside some of your income in a 401(K) plan and match your contributions.  Take advantage of this option to reduce the inconvenience of having to manually make deposits each month.  The method by which you set up automatic contributions will vary depending on your employer.  Talk to your employer’s accounting department to learn more about automatic payments at your workplace. The amount of money you decide to contribute automatically with each pay period is up to you.  The more you  put away each month, the more you’ll have to work with when you retire. In addition to employer-provided plans, put some of your income into other investment or savings accounts like an IRA.  Other retirement plans you might want to invest in include Roth IRAs, rollover IRAs, and Spousal IRAs.  Each type of account has different maximum contribution limits and different levels of taxation for withdrawals and earnings.  Since these contribution limits and taxation levels change frequently and depend on your age, consult a financial advisor for the most current information about the specific individual retirement account you’re interested in. You should be able to make automatic contributions to these individual retirement plans, too.  Talk to your employer’s accounting department for more information. Investing in stocks is a great way to make money.  Talk to a certified broker or financial adviser to get started.  Contact the stockbroker in your area who charges the lowest service fees.  Alternately, use a stock investment app to invest on your own.  Stock brokers usually require an initial investment that ranges from $1,000 to $5,000 USD (or more). You can start investing in stocks through some apps with as little as $5 USD.  Other apps will require larger initial investments.  Some of the most trustworthy stock market investment apps are Stash, Acorns, Betterment, and Wealthfront. Steadily add money to your stock portfolio to grow it over time. Robo-advisors (online services that use algorithms to manage your stocks, mutual funds, or ETF investments) tend to charge less than actively managed funds.  Even if you choose to go with an actively managed fund, choose one that charges the lowest possible investment fees. All stock investment entails some risk, but some investments are riskier than others.  For instance, if you invest in emerging foreign markets or initial public offerings (which are untested and possibly prone to volatility), you could lose your money.  On the other hand, riskier investments tend to have bigger payoffs if they succeed and their price rises.  For a safer investment approach, diversify your investments by choosing a mix of different industries (like tech, automobiles, and construction) and put most of your money in long-term mutual funds and ETFs. There’s no right or wrong way to balance your investment risk levels if you want to retire by 40.  Either a high-risk investment approach or a low-risk investment approach could work. Ethical investing means putting your money into companies whose beliefs align with yours.  For instance, if you’re a vegetarian, you might not want to invest in a fund that includes meat or fish companies. Ask your broker or financial advisor for a full list of the companies you’re invested in.  If you’ve invested through a robo-advisors, the list of companies you’re invested in should be available online.

Summary:
Set up automatic contributions to your retirement savings. Don't rely just on employer plans. Invest in stocks. Avoid high investment fees. Consider your risk level. Invest ethically.