To add a trigger to a template you go to the template page and click Set triggers in the action menu.
This will display a flyout where you manage the triggers for the template. If the template already have triggers they will be displayed in the flyout otherwise you will be asked to add a trigger. Click on the Add trigger button to add a trigger.
On this step you choose what kind of trigger you want to add to the template, Date & Time, Webhook or Manual. These options are described here.
In this example we add a Manual trigger by clicking on the Manual option.
The trigger is now added to the template and you can configure when it should trigger new checklists, for who and how the new checklists should be configured.