Tap is all about showing off the shoes. All the poses that you make needs to highlight not only the outfit but particularly the shoes. As mentioned in previous posts the best position to start off with in any pose is first position. This gets the dancers centered and ready to build upon other tap dance poses for pictures.
A simple pose you can use is to have the dancer point one toe up and then put both hands on there hips. Naturally they will bend over a little as there are putting weight on the opposite foot. From that same pose you can have them pull the leg that is extended out and have them cross it over the other foot. You can keep the upper body pose the same (hands on the hips) or you can have the dancer raise one arm and bend the wrist