I haven’t actually seen this book, by Christine Demmer and Heide Huck, but it was mentioned on the TV news programme this lunchtime.
There is a recommendation (in German) on the Berliner Morgenpost site.
The book discusses how to offer praise and criticism, how to deal with special jobs and special payments, how to register the job with the authorities if necessary, and above all: a large glossary with the most important expressions and sentences in the seven most common languages spoken by many cleaning women in Germany.
I would like to know which languages, and what expressions are the ones you normally use to a cleaner.
By the way, I believe that is a non-Islamic headscarf.