To create your own unique lesson plan I would first research some different types of career development lesson plans that are already available out there to get some ideas. In doing so, you can find something that will be of interest to both you and your students. With this said, I have attached the following lesson plan that I retrieved from the "Power To Learn" website. I will guide you through the elements needed and tweek on this plan to create a plan of my own for an example.
Title: Career Step Action Plan for High School
Materials and Resources:
Internet, career day visitors ...
Lesson plan designed to help students investigate career choices.