Successful investing doesn't have to be complicated. In fact, some of the most straightforward strategies can enable you to become a millionaire over time without breaking much of a sweat at all. If there's one thing that's true about investing, though, is that you have to be in it to win it. When it comes down to it, nothing beats simplicity for an investing strategy that you can actually execute.

With that in mind, here are four investing tips that are so simple, they're like magic. Follow them, and you'll greatly improve your chances of winding up financially comfortable vs. had you not invested at all. Sure, there may be more complicated strategies that might be able to edge out higher returns, but they'll likely require much more work and possibly risk attached.

Button with the word "easy" written on it

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No. 1: Start early

The earlier you start investing in your career, the easier it is to amass a large nest egg by the time you retire. The following table shows how much you need to sock away each month to wind up with a $1 million nest egg by age 65, depending on what age you start and what rate of return you earn.

Starting Age

10% Annual Returns

8% Annual Returns

6% Annual Returns

4% Annual Returns




































Data source: author.

By starting early, the amount you have to come up with out of your pocket can be substantially lower -- even if your returns don't keep up with the market's historical long run rates. In addition, if you think it's hard to come up with a couple of hundred bucks a month in your 20s, imagine how tough it will be to come up with a few thousand in your 50s to wind up in the same spot. Especially if you hadn't been investing before, it's tough to come up with that much money out of thin air after your habits are established.

No. 2: Make it automatic

Perhaps the most powerful tool most people have at their disposal when it comes to investing is their company's 401(k) or other employer-sponsored retirement plan. What makes it so powerful is that you can automatically invest in your employer's plan every payday, straight from your paycheck. You'll never see the money in your checking account, which makes it that much less tempting to spend.

In addition, many companies offer ways to boost your contribution over time, often through automatic annual increases or through setting your contribution as a percentage of your salary. With that type of plan setup, you'll be saving more every time you get a raise or every year, with just the simple one-time effort of agreeing to participate in the plan.

Keeping up with a plan consistently is as important as starting early when it comes to building wealth from investing over time. Making it automatic can go a long way toward helping you achieve that goal.

No. 3: Invest in an index fund

One of the simplest investing choices out there is also one of the most powerful -- invest your money in a broad-based index fund. Over time, index-based investing tends to outperform professionally active managed funds. It's such a powerful reality that even Warren Buffett -- one of the best stock-pickers alive -- won a million-dollar bet by choosing the side of index funds over actively managed hedge funds.

There's a powerful mechanical reason behind that trend. Professionally managed funds tend to have higher fees to pay for that active management. Those fees mean they need to outperform the market by more than their costs just to keep up with the index. On average, the market's performance is the performance of all the active participants in it, before their fees. As a result, it's an uphill battle for the typical professional money manager just to break even when compared with a relevant benchmark index.

From your perspective as an individual investor, it means that the simpler investment is very likely to be the better-performing one over time as well. With their ability to outperform because of their lower costs, index funds can certainly feel like magic, even though they're not.

No. 4: Keep investing regularly throughout your career

Although the earliest dollars you invest have the potential to grow the most, it is very unlikely that you'll be able to retire comfortably based on just the growth of those early dollars. By making regular investments every payday over your career, you boost the overall size of your nest egg.

Even better, you'll be dollar-cost averaging by making those routine investments. When the market is high, you'll be adding on top of your winners. When the market is low, you'll be buying that many more shares with every dollar you invest. Over time, that act of making steady investments will improve your chances of earning returns about in line with whatever the market happens to return.

In addition to the benefit of getting more money invested, dollar-cost averaging can be a powerful -- and simple -- way to help you get past the fear of investing near a market high. After all, if the market falls after your initial investment, your next one will get you in at a better value. If the market continues to rise, on the other hand -- well, the money you invested should grow right along with it.

These tips are the core of a remarkably solid investment plan

Taken together, these four tips provide the core of a simple, yet incredibly powerful, investment plan. It's so powerful, in fact, that even if the market's returns are lousy, you've got a good chance of winding up reasonably financially comfortable over time.

It may seem like magic, but it's not. It's just how consistent investing, following a reasonable strategy over a long period of time, works. The most important ingredient, however, is time. The more time you have to put toward this plan, the better things are likely to turn out for you in the end. So get started now, and let these tips work their "magic" for you for as long as they possibly can.