I might sit down and write up an informal agreement. Start with about $450.00 per month(or maybe more based on the information below) and spell out when it is to be paid by. If he needs to break it down into smaller payments, then arrange that. Tell him it is his legal obligation and the money is not for you, it is for your child. She is the one legally entitled to it.

If he won't sign, then tell him you are going to take him to court and you will ask for more. And you will ask for him to pay all associated costs because he is not being cooperative. Of course, you will only get what is decided, based on both of your incomes. I might try to garner information about what he makes before you approach him so you will have some standing with the court if he tries to get paid under the table after you file. I found the following for your state:

As an example, let’s say you have the majority of physical custody of your one child and you make $20,000, while the other parent makes $30,000. After adding your incomes ($50,000), the court multiples that total by a percentage per child, or “child support percentage.” These percentages are:
•17% of the combined parental income for one child,
•25% of the combined parental income for two children,
•29% of the combined parental income for three children,
•31% of the combined parental income for four children, and
•no less than 35% of the combined parental income for five or more children.

In our example, the court would multiply $50,000 x .17 = $8,500. That product ($8,500) is the basic child support obligation. You would be responsible for 40% of that figure ($3,400) because your income ($20,000) makes up 40% of the combined parental income ($50,000). The other parent would be on the hook to pay 60% ($5,100). This means that the other parent would have to make payments to you over the course of the year that add up to $5,100. Because you have physical custody most of the time, the court will presume that you are spending your share directly on your child’s expenses.

In addition to the basic child support obligation, the court may tack on additional payments to cover child care costs if the custodial parent is working or going to school and for the child’s reasonable health care expenses. These payments are prorated at the same percentage as the support obligation (using our example, 40% and 60%). The court may also order payment for the child’s education.

You HAVE to do this for your child. Please don't wait. He may end up owing back support and will be ordered by the court to pay it. Then what? He won't have it and you will have a bigger mess on your hands. It is your job as her mother to collect child support! Good luck and big hug.