Simply open the relevant Plan in BC-3, then click Create Incident:
The incident shell will then pull out the processes and recovery phases outlined in your plan. You can now add details of the incident (name, start date/time), and select the recovery phases and strategies, any processes that are relevant, and add some general comments on the incident. When you're done, click Create at the bottom of the screen.
The incident is now ready for anyone associated with the plan to use. You can click on the link to open the incident in your browser. It will also be accessible from the home page on web or mobile view.
See article on Incident Management module for more information.