Begin with a precise question and work from the known to the unknown
Start with yourself or the most recent well-documented relative and move backwards one relationship at a time. Write down the exact person, place, period and question you are trying to resolve before searching. Interview relatives with permission, record who supplied each memory and keep living people private. Names, family stories and online trees are useful leads, but they remain hypotheses until records and careful comparison support the identity or relationship.
Search broadly, inspect the original record and cite what you actually used
Use civil registration, parish registers, censuses, probate, newspapers, migration, land and military records according to the place and period. Search spelling variants and nearby relatives, then open the image or original record instead of relying only on an index. Save the repository, collection, volume, page or image, stable link and access date. Separate what a record states from the conclusion you draw, and record negative searches so the work can be repeated.
Build a family tree that preserves uncertainty, review and portability
Connect each name, event and relationship to its supporting citations and keep contradictory dates, spellings or parents visible until the evidence has been weighed. Document why one conclusion is preferred without deleting competing source statements. Use research tasks and a log for unresolved questions, give collaborators only the access they need, and keep independent exports of irreplaceable research. A clear audit trail makes the tree easier to correct, share and continue over generations.