I've got a weighted hoop which is designed for exercise, it came with a DVD showing the correct way to hula hoop and this really helped me. As for it being an effective method of exercise, I think it's a bit overrated, at least as a form of cardio because I could be hula hooping for 10-15 minutes and not feel worn out whereas if I were jogging for that long I'd be knackered. That said, the DVD also had a workout on it which I've never done as I have now lost said DVD so that may have proved more difficult!