Some pipe dreams are never likely to come true, such as getting drafted to play on a professional sports team or winning a lottery jackpot. Other pipe dreams are much more achievable than you might think -- such as retiring with a million dollars. Here are three ways to get to that million. For best results, if possible, act on all three. Image source: Getty Images. 1. Start early The sooner you start investing for your future, the better -- even if you're only, say, 20 years old. The longer your money has to grow, the more it can grow for you, so your earliest invested dollars are your most powerful ones. Check out the table below, which shows the power of time with a single $1,000 investment (not $1,000 per year). It assumes an average annual growth rate of 8%, which is a bit conservative, as the average stock market return over long periods is close to 10%. Over This Period... $1,000 Will Grow to: 5 years $1,469 10 years $2,159 15 years $3,172 20 years $4,661 25 years $6,848 30 years $10,063 35 years $14,785 40 years $21,724 45 years $31,920 50 years $46,902 55 years $68,914 60 years $101,257 Calculations by author. The more time you have, the more money you can amass. Image source: Getty Images. 2. Invest aggressively You're probably not going to average 8% annual growth if you're socking away lots of dollars in a bank account or certificates of deposit (CDs), or even most bonds because interest rates these days are extremely low, often well below the rate of inflation. There's a chance that interest rates will rise and stay at high levels for much of your investing time frame, but don't count on that. Instead, count on the fact that, overall, stocks have outperformed bonds over most long periods. According to the research of University of Pennsylvania professor Jeremy Siegel, stocks outperformed bonds in 96% of all 20-year holding periods between 1871 and 2012, and in 99% of all 30-year holding periods. It's also important to invest relatively large sums regularly, for best results. The table below shows how much you might amass if you do. Growing at 8% for $10,000 Invested Annually $15,000 Invested Annually $20,000 Invested Annually 5 years $63,359 $95,039 $126,718 10 years $156,455 $234,683 $312,910 15 years $293,243 $439,865 $586,486 20 years $494,229 $741,344 $988,458 25 years $789,544 $1,184,316 $1,579,088 30 years $1,223,459 $1,835,189 $2,446,918 Calculations by author. 3. Stay inspired and stay the course Finally, once you start socking away money for your future, it's critical to keep doing so. It's very easy to get distracted or discouraged if you don't see big results right away. And you most likely won't see big results right away. Check the tables above, and you'll see that the big growth happens in later years -- but you have to put in the earlier years to get to the later ones. Becoming much wealthier is very likely within your reach, especially if you have many years until retirement. But even if it's just a decade away, you may be able to improve your future financial security to a meaningful degree. 10 stocks we like better than WalmartWhen our award-winning analyst team has an investing tip, it can pay to listen. After all, the newsletter they have run for over a decade, Motley Fool Stock Advisor, has tripled the market.* They just revealed what they believe are the ten best stocks for investors to buy right now... and Walmart wasn't one of them! That's right -- they think these 10 stocks are even better buys. See the 10 stocks Stock Advisor returns as of 6/15/21The Motley Fool has a disclosure policy.Source