So you've got a workplace 401(k). Congrats! This account is one of the best tools to save for retirement because your employer does the hard work of setting it up for you and may even help you make contributions to it.

But while it's good news that you've got access to a 401(k), it can be daunting to figure out what to do with it. Fortunately, these plans are specifically designed to be easy to manage. In fact, by taking just a few simple steps, you can use this account to set yourself up for a financially secure retirement.

Here's what you need to do. 

Piggy bank with colorful 401(k) letters next to it.

Image source: Getty Images.

1. Find out how your employer match works if you have one

If your employer offers a 401(k) match, this is the single biggest benefit of a 401(k). An employer match is literally free money, because you just have to contribute to your account and your employer will also make a contribution on your behalf. 

There are different approaches to employer matches. For example, some companies provide a 100% match up to a certain percentage of your salary, while others may provide a 50% match. Find out what your employer offers by asking human resources or your plan administrator. Whatever the amount, contribute enough to max out the match in order to get all the free money you can

2. Set up (or increase) your contributions

In some cases, you'll be automatically signed up to have 401(k) contributions withdrawn from your paycheck unless you opt out. In other workplaces, you have to opt in. Find out what the rules are by asking your plan administrator or HR and see what, if anything, you're currently investing. 

Ideally, you should aim to deposit around 15% of your income in your retirement account. If you aren't saving that much yet, increase your contributions at least a little ASAP. If you're already signed up to have 6% of your pay invested, notch that up to 7%. You probably won't miss the money. Then in a few months, you can go up to 8%, and so on. 

If you aren't currently contributing anything at all, take a close look at your budget, decide how much you can afford, and complete the necessary paperwork to start moving money into your account. HR or your plan administrator can provide details on how to do that, and it's usually a simple process you can do online.  

When you set up automatic contributions from your paycheck, do it based on a percentage of your salary rather than a flat amount (i.e., sign up to invest 5% of income instead of $500 per month). That way, the amount will automatically go up as your salary does. 

3. Pick the right investment mix

Once you've got money going into your 401(k), you must decide how to invest it -- otherwise, it'll just sit idle. Most 401(k) plans offer limited investment options, so this shouldn't be too hard.

You may find your account offers a "target date" fund, which is a really simple option. With a target date fund, just pick the one that matches your projected retirement date. Your money will be invested in an appropriate mix of assets based on your age and timeline, and your asset allocation will change automatically as you get closer to retirement. Target date funds are a very hands-off approach and could work well if you don't want to do anything to manage your account. 

On the other hand, you may also decide you'd prefer to take a little more control over how your funds are invested or may not want to pay fees associated with the target date funds your plan offers. You'll usually have a mix of exchange-traded funds or mutual funds to choose from and can distribute your contributions among them. Research each option carefully to assess past performance and compare the fees you'll pay when you make your decision. 

By making sure you're contributing enough and choosing the right investment mix, you'll maximize the chances your 401(k) balance will grow large enough to provide you with a comfortable income as a retiree.