The vast majority of retirees work and save their entire adult lives in order to be able to slow down and enjoy their golden years. Unfortunately, many people fall behind and struggle to have enough money saved up by the time they want to retire.

Find Out: The 1 Thing You Can’t Do With Your Required Minimum Distributions in Retirement

Learn More: How Much Money Is Needed To Be Considered Middle Class in Every State?

According to an AARP survey last year, 20% of Americans over the age of 50 have no retirement savings, and over half worry they won’t have enough money to last through retirement.

GOBankingRates recently spoke with Frank H., and while he was never part of the 20% with no retirement savings, he said he made some mistakes along the way. Better yet, he shared three things that he would focus on if he had to do it all over again.

Keep reading to find out how you can learn from Frank and better prepare for your own retirement.

“When I first started working after college, 401(k) plans didn’t exist,” said Frank. “They weren’t developed until the late 1970s, and I didn’t have access to them until the 1980s. Instead, I was putting money away into a personal savings account. I hoped it would supplement what I would receive from Social Security.”

Frank continued, “The problem was that I didn’t really have a plan. I didn’t know how much I was going to need; I was just blindly putting money away.

“Things are a lot different today. I talk to my son and he has a retirement number. He knows how much he wants to have saved by the time he retires, and based on historical returns, he knows how much he should be saving each month.”

Having a plan is one of the most important things you can do for your retirement. Understanding how much money you’ll need each month to afford your retirement lifestyle can help you figure out how much you’ll need in your retirement account before you can retire.

Read Next: 6 Cash-Flow Mistakes Boomers Are Making With Their Retirement Savings

“By the time Roth accounts were created, I had been working and saving for [over] 20 years,” said Frank. “However, I wish I had understood their power much sooner.”

Frank continued, “Most of my retirement savings (other than Social Security) is in either a traditional 401(k) or IRA. When I make distributions, a significant amount is taken away for taxes. This was something that I didn’t take into consideration when Roth accounts became available.”

Traditional retirement accounts are a great way to save for retirement, but they require some additional planning. When you make contributions, it helps lower your taxable income in the year the contributions are made. However, you must then pay taxes on the earnings when they’re withdrawn.