What are options for boosting my credit score without getting retail credit cards after a DMP?

Question: My credit took a massive hit when I graduated from college. I signed for a debt management program at the age of 26! Now I need options to boost my credit without getting retail credit cards. What are my options? I have one final account to settle through my DMP which I am hoping will happen within the first quarter of 2020.
Dear Reader,
Congratulations on almost reaching your goal of becoming debt-free! That’s a fantastic accomplishment. Going through a DMP probably has affected your credit in some ways. How much and in which light, depends on your credit history before and during your DMP. For instance, closing your credit card accounts when you enrolled on the DMP probably hurt your score, but consistently paying on time during your program should have had a positive impact.
You have several options to rebuild your credit. You can start by correcting mistakes in your credit reports. Get a free copy of your credit reports from each of the major credit bureaus (Experian, Equifax, and TransUnion) through www.annualcreditreport.com and carefully review them to make sure they are error-free. If you find mistakes, start a dispute online through each of the credit bureaus’ websites to correct them.
Next, you need to get new credit and learn to use it strategically. There are several ways that you can do so. One way is to become an authorized user in someone’s credit card. When you become an authorized user, the credit card activity is included in your credit history, and depending on how the account is managed, it can build or hurt your credit. Another option, and arguably your best option, is to get a secured credit card and use it strategically. This type of card is backed by a deposit you make that also serves as your credit limit. It’s best to put a small, recurring charge on it and always pay on time. Just keeping your balance low and paying on time are the two most important things you can do to boost your score. These cards are also your gateway to regular credit cards in the future, so be wise.
Similar to secured credit cards, many credit unions and banks offer starter loans to help you establish credit. Yet another option is to have a friend or family member co-sign a small loan with you. In this case, you and your co-signer are both equally and legally responsible for repaying that loan. Other options can include rent/utility reporting services. There are a few of them out there, but most charge a setup fee and monthly payments to report your payment history. So, make sure you carefully review them and see if they are worth it and if they report to the three credit bureaus. Similarly, Experian Boost is a free service that can include the payment history of some of your utilities and telecom bills in your credit report to give your score an extra boost. However, Experian Boost only reports to your Experian credit history, so your TransUnion and Equifax scores won’t see the same benefit.
You have several options to rebuild your credit. Which strategy is best for you depends on where you stand right now. You can always talk to a nonprofit credit counselor to get a personalized plan. Counselors can review your credit online and over the phone and help meet your financial goals. Finishing paying off your debt is just your first step. Good luck.
Sincerely, 
Bruce McClary, Vice President of Communications
Bruce McClary is the Vice President of Communications for the National Foundation for Credit Counseling® (NFCC®). Based in Washington, D.C., he provides marketing and media relations support for the NFCC and its member agencies serving all 50 states and Puerto Rico. Bruce is considered a subject matter expert and interfaces with the national media, serving as a primary representative for the organization. He has been a featured financial expert for the nation’s top news outlets, including USA Today, MSNBC, NBC News, The New York Times, the Wall Street Journal, CNN, MarketWatch, Fox Business, and hundreds of local media outlets from coast to coast.