I started by just setting stationary and holding myself up next to my car where I practiced clipping in and out about 40 times on each foot. Then I went to a parking lot and practiced by starting off and going 10 or 20 foot and stopping. I did this until I was completely sure of my ability to un-clip. I've made a habit of always unclipping my left foot as I come to a stop. I started by uncliping early and anytime I reached for the brake. I've fallen once when I pulled off a road into thick sand which brought me to a instance stop and down I went. Had a couple of other close calls, usually when I have to make a emergency stop or as I run out of forward momentum on any kind of incline. At this point(5000 miles later) unclipping has pretty much become second nature, but It would not surprise me to get in a situation where I went down again.