The workflow involves the following steps:
Dividing an image into segments
Computing various attributes for the segments
Creating several new classes
Interactively assigning segments (called training samples) to each class
Classifying the entire image with a K Nearest Neighbor (KNN), Support Vector Machine (SVM), or Principal Components Analysis (PCA) supervised classification method, based on your training samples.
Exporting the classes to a shapefile or classification image.