Another good way to stay motivated is to spend money on yourself before paying your bills.
Though somewhat counterintuitive, this way you'll see exactly how much extra money you need each month to satisfy both of your objectives: fulfilling desires like buying that vintage guitar you've had your eye on, and meeting your bill collectors' demands.
This doesn't mean you should rack up lots of credit card debt, but do keep “paying” yourself first; the extra pressure of paying off your bills afterward will inspire you to find creative ways to make enough money to satisfy both.
This method will also sharpen and develop your financial self-discipline, which is a key trait of all financially successful people.