After initiating the process of merging, the patron list will show records that match and alternate the colours if the record indicating which groups it thinks match. They are shown in dark red and dark cyan - colours that are different from normal colours used on the patron list.
It is suggested that you only show the possible duplicates in the list. If you chose to leave others within the list, they will show between the groups in their original colours.
Merge the resulting list according to: