Ask those attending to bring colored pencils or crayons and a straignt edge or ruler. Then you can provide the graph paper. That covers design and color theory simplified.
The rest I would do as a talk with a the main points in writing to give to each person attending. Sometimes I leave room for the 'students' to write their own notes.
Bring your own samples to show, such as: 4 patch, 9 patch, HST's, sandwiching, and binding. Maybe even include some sewing machine feet that they may want to consider using: 1/4" foot, 1/4" foot with flange guide, and open toed foot.
Hopefully there will also be some nice snack foods for your 'students'. Somehow we seem to remember best when other memories are triggered.
ali