1. An automated stainer for staining, in particular for hemalum-eosin (HE) staining, of a histological sample, the automated stainer exposing the sample to the action of at least one stain using at least one staining parameter, wherein the automated stainer comprises: an input apparatus with which a staining parameter is defined by a user or selected from a plurality of possible staining parameters; and a control apparatus which, upon definition or selection of the staining parameter, is configured to ascertain a prospective expected outcome of an action of the staining parameter and display the prospective expected outcome to the user with a display apparatus before the automated stainer stains the sample.