For versions of the module 1.2.0+, the "soleilsign" pdf template is activated automatically after module activation, the following manipulation is therefore unnecessary for these versions.
After activating the SoleilSign module in the Modules / Applications list, you must also activate the "soleilsign" template added to the Interventions module.
In the list of Modules / Applications, open the configuration page of the module Interventions.
In the list of document templates, look for the "soleilsign" template.
Turn it on.
Make a first test by clicking on the "preview" icon.