The State Archives of North Rhine-Westphalia has published a brochure, with important and useful tips for genealogy and the right way to your own family tree.
From the contents:
Step by step to the "family tree"
Reading tips for getting started
Genealogy networked - useful addresses
The people in California state archives
The personal archive as Rhineland in Brühl and its holdings
The personal archive as Westphalia-Lippe in Detmold and its holdings
What are church records, Church book duplicates, Civil Registry and Civil Registration?
With the edition after edition of Brühl and Detmold in search ancestors
How you can participate in the edition: The "Verkartungs" project of the Detmold Edition
The services of persons as archives Rhineland and Westphalia-Lippe