Most financial planners will advise that those wanting to pay off their debt do so by beginning with the bill that has the highest interest rate. This make sense of course, if you look at the math. But psychological point of view, the opposite can be true where 5 debts will be seen as more than 2 debts. For this reason many people fail as they never get away from that feeling of being in debt over their heads.
Starting with the highest interest rate first do work for some, but not all. For many, that bill with the highest interest rate is also the bill with the highest balance. Paying on this bill first will show little results for months and psychologically will work against you.
If you begin with the smallest debt first and pay extra toward it first, this will give you the satisfaction and sense of success that will help to keep you going and not giving up. Start small and adding as you go along, like building a snowball. This plan is for those who have tried the other way already and failed.