One of the largest data breaches in history has left 143 million people wondering if their highly personal data has been exposed to hackers. For now, Equifax doesn't explicitly tell you if you were a victim, and in 99.99 percent of cases (yes, literally), it won't notify you by direct mail. But, if you're concerned you're vulnerable to identity theft because of the breach, this guide is for you. 

Read more: Everything you need to know about the Equifax hack

But first: A quick recap

Equifax, one of the three major credit bureaus, lost control of customer data that included social security numbers, home addresses, credit card numbers, drivers license numbers and birth dates. The company estimates that the data of 143 million people were exposed, which equals roughly half the US population. That means that the chances you are affected are pretty high.

Even though Equifax set up a program to help people protect their potentially-exposed data, it might not give everyone complete confidence in keeping their identities secure. Here's why:

• Equifax's enrollment program doesn't explicitly tell you if your data was a part of the breach. The company only makes it clear to those who weren't exposed. It's confusing. (We reached out to Equifax for comment and haven't heard back.)
• The breach could have started as early as mid-May 2017. That means that the data of 143 million people were exposed for more than three months. It's unclear what the hackers did with the data during those months. 
• Those who would like to be prudent about protecting their identity might have to wait a week before they are officially enrolled in Equifax's protection program. For some, that's just not fast enough.

You don't have to wait to enroll in Equifax's program to start protecting yourself against the hack. Here's what you can do. 

Step 1: Enroll in Equifax's program

Equifax's own identity protection program isn't perfect, but it will help ensure you're using every available resource to protect your identity. We put together a guide on how to follow the program here. Note that even if the enrollment tool indicates you weren't exposed, you're still eligible for a free one-year subscription to Equifax's protection services. (Not a bad idea given the frequency of breaches.) 

Some language in the terms of service for Equifax's program, Trusted ID, have raised concerns that enrollment in the program prevents consumers from participating in a class-action lawsuit. CNET is looking into this and reached out to Equifax for comment. We'll update this story when we know more. 

Step 2: Check your credit reports

More than three months passed between the time the breach may have started and now. We're not sure if the data of those affected was used maliciously during that period, so consider looking through your credit reports for any suspicious activity. The federal government guarantees everyone a free annual credit report from the three major bureaus -- yes, including Experian. You can get those reports here.

When looking through your reports, keep an eye out for new accounts you didn't open, late payments on debts you don't recognize and any other activity that looks unfamiliar. 

If you suspect someone used your identity to open credit cards, take on loans, or re-open closed accounts, contact the credit card company's fraud department immediately. You are not responsible for charges made on a fraudulent card, but you have to report the issue in a timely manner. Once you've reported the fraudulent credit, follow this guide to recovering from identity theft. 

Step 3: Freeze your credit

It's still early days, so even if your credit report comes back clean, remain vigilant about protecting your credit. One of the most reliable ways to prevent someone from opening credit cards in your name is to place what's called a "credit freeze." 

When you freeze your credit, you (or anyone masquerading as you) will be required to un-freeze your account by providing the PIN you got when you froze your credit. 

To freeze your credit, contact each of the credit bureaus using these phone numbers:

The process is usually automated and can be completed within a few minutes. Just be sure to write down your PINs in a secure place.

Step 4: Set a fraud alert

A fraud alert is another way to make it hard for identity thieves to open accounts in your name. When a fraud alert is set, credit card companies will be required to verify your identity before opening an account. That, combined with the credit freeze, is a great way to keep your credit secure.

To set a fraud alert, contact just one of the credit card bureaus and ask for an initial fraud alert. Once the alert is set, it will last 90 days. After that, you'll have to renew it. Here are the appropriate phone numbers for the bureaus (remember, just call one):

Step 5: Repeat the process for your loved ones 

Because Equifax is not notifying those affected through direct mail or email, some people will be left without the resources or tech-savvy to protect their identities or find out if they were compromised. With that in mind, consider helping your loved ones -- especially the elderly without computer access -- with the above steps. 

Watch out for tax season

It's still to early to know if and how the data exposed in Equifax's breach will be misused, but one major concern comes around during tax season. Identity thieves can use stolen social security numbers to file fraudulent tax returns and receive refunds. 

Many victims find out they have been targeted in tax fraud when they try to file their taxes -- the IRS tells them that their taxes were already filed. One of the best ways to prevent this from happening is to file early. For more, the IRS has an easy-to-follow guide on tax fraud.