Below is a video that was created to demonstrate a workflow for designing sports pitches in Civil 3D.
The basic workflow is to create 3D linework (featurelines) to define the outline of the pitches, applying the proposed levels at the corners as we create them. The grading of the pitches was at either 1/100 or 1/140 and we can apply this as we create the featurelines, grading tools weren't required. The boundary featureline is created by snapping to the existing ground surface along the site boundary line. (you can quickly do this by turning the boundary polyline into a featureline and get it to pick up the levels from the existing surface). We then simply added all these featurelines into a new surface to create our proposed surface.
The volumes were then balanced by raising or lowering the featurelines as necessary, keeping an eye on the numbers in the volumes dashboard until they are close.