Reputable credit counseling organizations can advise you on managing your money and debts, help you develop a budget, and offer free educational materials and workshops. Their counselors are certified and trained in consumer credit, money and debt management, and budgeting. They discuss your entire financial situation with you, and help you develop a personalized plan to deal with your money problems. An initial counseling session typically lasts an hour, with an offer of follow-up sessions.
Find a good credit counselor. Almost all DMPs are administered by consumer credit counseling agencies--so much so, in fact, that the terms "credit counseling" and "debt management" are often used interchangeably. Thoroughly researching the agency is the most important thing to do before deciding to enroll in their debt management program. The FTC has put together a simple guide to help you get started and choose the right plan.
However, carrying a large amount of debt that is difficult to repay also negatively impacts your credit score. For example, debt from student loans can accumulate and increase over many years of nonpayment. So, you have two choices in such desperate situations: pay off your debt from student loans slowly, missing minimum payments and taking damage to your credit score or hire a debt relief company, settling the debt from your student loans faster while taking a hit to your credit score.

As far as options go, I’d recommend you start by talking with a reputable credit counseling agency – one of the options I mentioned in the story. That will give you a baseline to start with. If they can help you with DMP, it’s likely to do the least damage to your credit (with the exception of just paying the debt off) over the long run. If you/they determine a DMP isn’t feasible then you’ll know you have to look at more drastic options like negotiation or bankruptcy.
The big advantage of the debt snowball is scoring quick wins. Science backs up the idea that this is the best approach, because you'll stay more motivated as you see debt balances paid off. But there's an obvious downside: Your smallest debt may not have the highest interest rate. If you're waiting longer to pay off high-interest debt while focusing on lower-rate debts, you'll pay more interest over time.  
In fact, certain aspects of a debt management plan will have a positive impact on your credit score. These aspects are the amounts owed, payment history, and inquiries for new credit.  Your payment history, which makes up 35% of the FICO credit score, will have a positive impact assuming your payments are made every month. In terms of amounts owed, which makes up  30% of the Fico score, this aspect will be positively impacted as the accounts are paid down.
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