I don't think this kind of training should be too serious. The more relaxed the atmosphere, the better, which is more helpful to attract students' attention. You can make some jokes at the beginning, such as asking others what they think of your image, and what kind of image you think can attract others' attention at first sight. Because you are talking to college students, you can get more exposure to college life, such as some social clothes (after all, I'm not a professional and I don't know something, so you can think about what can interest you). Don't be too rigorous in the whole process. It is best to interact with students, which will have a good effect. Finally, you can praise everyone appropriately, such as hoping that girls can attract the attention of others, boys can be more mature and elegant, and so on. With a little joking tone, it will not make people feel fake, but also make everyone feel happy. That's all. I hope it helps you.