A club administrator can add new instructors by going to Club Admin > User Admin > Add New. When adding the user, be sure to select Role: Instructor to allow them instructor privileges within the club.
If the instructor has an existing StagesFlight account, make sure they have added the club ID to their account. If they are listed as a user of the club, simply go to Club Admin > User Admin > Search to find the user. Once you've located the user you'd like to make an instructor, click the edit button on the right-hand side of their account information and change their Role to Instructor.
After you've created the instructor account, your new instructor simply needs to log in to their account and go to the Instructor tab and create a new profile or route. Once an instructor's first route or intensity profile is created, their instructor profile will show up on the StagesFlight instructor console within your club.