The template was designed to default to

if no parameter is given. In the following table, the first column contains the header and the second column shows the template call used to create it.

There are no parameters in this template.

From the Alexander Fleming article:

{{s-start}}
{{s-aca}}
{{s-bef | before = [[Alastair Sim]]}}
{{s-ttl | title = [[Rector of the University of Edinburgh]] | years = 1951–1954}}
{{s-aft | after = [[Sydney Smith (forensic expert) | Sydney Smith]]}}
{{s-end}}

• Documentation for creating succession boxes can be found at Template:S-start.