Always stain one slide first and check banding quality before staining additional slides. Adjust trypsinization time if necessary. Be careful not to over rinse slides since over rinsing will fade stain. Leishman's stain will form a precipitate when added to pHydrion buffer. Therefore, the two should not be mixed until just prior to flooding the slide.
Rinse slides with absolute methanol and allow to dry completely.
Wright's stain may be used in place of Leishman's stain. References Seabright, M. Rapid banding techniques for human chromosomes.