Child Support by Separation Agreement

My ex-spouse and I entered into a separation agreement before the divorce was final in 2012. It outlined the child support terms we agreed to. Must I use NC Child Support Enforcement to collect or can the payments be made as outlined in the separation agreement. We had the agreement notarized but it was not filed in court with the divorce decree. If the latter, is fine, assuming no chaos or conflict begins, is there anything additional either of us should do to document payments, other than basic record keeping?

What needs to be done if we modify it for increase?

This is the agreement:
4.1. Child Support. Husband shall pay to Wife as monthly child support the sum of $100.00 per month on or before the 15th day of each month with the first payment, due and payable on or before the 15th day of the first month following the execution of this Agreement, and a like payment monthly thereafter. Husband agrees to notify Wife when there is a change in his employment and agrees to furnish Wife his paycheck vouchers at such time and every six months for the purpose of reviewing the child support payment for increase.

Thanks.

You can pay your child support obligation directly to the other party. You should pay using checks and keep track of all of your payments made.