Dog Health Questions: Dog training problem?

My dog knows quite a few tricks: sit, lay down, speak, shake. Just recently i taught 'roll over.' I have developed a small problem. I've read that you should teach play dead BEFORE roll over, but I didn't. How can i teach her 'play dead' without confusing her?

Improve Your Training Sessions With These Dog Training Tips - Part 1

Recommended Answer:
you should stop her mid-roll while she is on her back by putting your hand on her tummy for a few seconds. then say 'good girl'. then after she gets up give her a treat.

Dog Training Tips - How To Get The Most Out Of Your Dog

• Before you do those things, you need to teach your dog to sit, and to stay, and to come when called. These are commands that one day may save your dog's life. I've also heard of a command, like a super come command, for emergencies when it is absolutely imperative that your dog obey you right now. You would use an unusual word different from come, such as whoop-ti-doo, or other uncommon term, and when he does respond by coming immediately, you give him a very special reward that he'd REALLY enjoy, like a can of real chicken. This way, the dog is protected when he runs into the highway, for instance.