"What exactly needs to be done" is up to your activity's contract policy office. Ordering procedures and responsibilities are largely left up to the components (services and agencies). That being said, I don't think it should be a major issue for orders under the micropurchase threshold. FAR 13.201(a) makes it clear that Agency heads may delegate micro-purchase authority, and we see this as cardholders frequently make micro-purchases. However, agencies establish varying levels of approvals, designations, documentation, and training before non-warranted ordering officers can make micro-purchases. This is why it's important that you consult with your local contract policy office to determine what needs to get done before the users of the bus service contract can place their own orders.