Creating an invoice routing category Invoice approval categories are used by invoice routing approval rules that use routing by role. Select AP Administrator > AP Automation Setup > Invoice Routing Categories. Click New. Specify this information: Invoice Routing Category Specify a name for the invoice routing category. Description Specify a description for the invoice routing category. Click Save. Create Invoice Approval Assignments. Click New and specify this information: Finance Resource Select the actor or resource to whom the role is applied. Invoice Approval Role Select the role to apply to the resource. Click Save.