Start with place, time and jurisdiction
Locate the townland, civil parish, religious parish and county whenever possible. Irish surnames are widely repeated and spelling varies, so a place and associated relatives are stronger anchors than a name alone. Remember that modern Northern Ireland and the Republic of Ireland require different repositories for some later records.
Follow the strongest record sequence
Search civil births, marriages and deaths, then use church baptisms, marriages and burials to move earlier or fill gaps. The 1901 and 1911 censuses, valuation material, wills and surviving estate records can rebuild households where other archives were lost. Search spelling variants and inspect register images when provided.
Preserve evidence and local context
Record the registration district or parish, event type, date, volume or page, archive and image URL. Respect statutory age limits on civil images. Preserve witnesses, sponsors, occupations and townlands because clusters of associated people often provide the evidence needed to separate families with identical names.