1. By Market - Your groups could be market driven, so for example your groups could be: domestic market, commercial/business market, construction market etc.
2. By Audience - Your groups could be based around the target audience demographic information, so for example: young men, trade customers, elderly men, construction managers etc.
3. By Service - Your groups could be based around the services you offer, so for example: key changes, lock repairs, commercial locksmith services, touch locks and other products etc.