I think you wanna talk (fake) not fixed, right? Of course, you can lay-up (勾手) fake people. However, you must not jumping. That means, your two feet must stay on the ground and one of them must not moving. If you do that, that's not foul.
Its ok for short player (矮ge人) use lay-up. However, because you are short, it is easy for other people block you (guard 臭!). So, just be careful and avoid people block you when you lay-up.
In fact, short player can have advantage (有利). Short people can run faster then tall people (normally), so they can avoid tall people easily.