The Commission for the Conservation of Antarctic Marine Living Resources has recently decided to re-adopt the generalised yield model (GYM) as an assessment tool to progress the management of Antarctic krill (Euphausia superba). To this end, the GYM has been re-implemented in the open source R package Grym. This document describes the model parameters required to conduct a krill stock assessment with Grym and, where possible, provide guidance as to how these parameters can be estimated.