”在天桥上走模特步“怎么说？

thanks for your advice, for a model that most important thing is to understand the cloth she is wearing and express the emotion from her understanding to the audience. It is of course not 1-1 communication, but like mass media. It is called " communication" too. For example, a same mini skirt, you can walk in it wildly or seriously giving differnt styles sometimes because of the different way you wear it. Thus, to give a fashion show a model has to have a very comprehensive knowledge of expressions, like the actor/actress. the purpose of the show is to let people see :-)

我认为这么翻译比较好:

at sky bridge up go model step, 大家意下如何?

"catwalking in fashion shows" should be fine. I have a friend who used to be a top model in China, now reading MBA in the States. If you emphasis on what you learned from this unique experience, you surely stand out from other candidiates.