Start with place, time and jurisdiction
Identify the parish, municipality and farm or residence before searching broadly. Norwegian names can combine patronymics with farm names, and a farm name may change when a person moves. Search several name forms and use the place as the stable clue that separates people who share a given name and patronymic.
Follow the strongest record sequence
Start with nationwide censuses to place a household, then follow scanned parish registers for baptisms, confirmations, marriages and burials. Digitalarkivet also exposes emigration lists, probate material, property sources and other archives. A bygdebok can supply leads, but verify its family reconstruction against original records.
Preserve evidence and local context
Cite the parish, register type, date range, page or image and archive reference. Transcribed searches are valuable navigation aids, not substitutes for the scanned entry. Preserve farm names, witnesses and godparents because they may reveal kinship networks even when the record does not state a relationship directly.