Transportation from Geneva Switzerland to Annecy France

My husband and I want to do a day trip to Annecy from Geneva in October. We won't have a car. I've heard going there by train is complicated and too long. Taxis are too expensive. The "packaged" 1/2 day and full day trips to Annecy seem to only be offered on Saturdays and Sundays in October and the only day we can do this is a Friday. When I searched for buses between Geneva and Annecy, buses to and from Nyon were listed, not Annecy. I've read about shared rides but am concerned this might be too complicated to arrange and not safe. I'd appreciate any ideas people might have. Thanks!