To add this template to, for example, Category:1910s births, use the following wikitext:

{{Birth decade category header|19|1|20th}}

The parameters are:

  1. All the digits of the decade except the last 2
  2. The next-to-last digit of the decade
  3. The century the decade is in, as an ordinal number (e.g., 1st, 2nd, 3rd, 19th, etc.)