First impressions count. This is the message Swiss bank UBS AG is sending its Swiss retail banking staff with a 43-page code dispensing advice on how to impress customers with a polished appearance.

Echoing rules applied at Swiss boarding schools, UBS's guidelines go beyond a list of dress "do's" and "don'ts" by providing hygiene and grooming tips often dotted with aphorisms worthy of fashion and beauty magazines.

The...