This disclosure describes, among other embodiments, systems and related methods for selecting electrode combinations to be used during nerve pacing procedures. A first set of electrode combinations of a nerve pacing system, such as a phrenic nerve pacing system for diaphragm activation, may be mapped (or tested) to determine the location of the electrode combinations relative to a target nerve. Once the general location of the target nerve is known, a more localized second set of electrode combinations may be tested to determine the most suitable electrode combinations for nerve stimulation. At various stages of the mapping process, electrode combinations that are non-optimal may be discarded as candidates for use in a nerve pacing procedure. The systems and methods described herein may allow for the selection of electrode combinations that are most suitable for stimulation of the left and right phrenic nerves during diaphragm pacing.