Select a NURBS mesh to trim. Specify options in the Control Bar. If the Freehand option is set, then press down the left mouse button on a View window and draw the trim curve over the NURBS mesh while holding the left mouse button down. Otherwise click a number of points on a View window and accept the tool by selecting Accept on a View window's popup menu or by clicking the Accept button on the Control Bar.
The Trim Curve tool has the following options: