when you're 50, falling isn't a laughing matter.. well, sometimes it is, and sometimes it isn't.
I took a lesson from someone at BikeUniversity here in my town, and i never fell once. We practiced riding WITHOUT clipping in, then clipping in and out, one foot, then both feet.
When i rode down the road back then i practiced constantly, taking them out, putting them back in, and noticed which foot i took out first. we're all different some people do right and some do left.
practice.