All you have to do is think really hard that you can't stand any other house, will not find your fellows there, will not reach your full potential...
Anyone who tries to manipulate Sorting Hat at age of 11 would automatically and deservingly be sent straight into Slytherin.
Update: This post has also been superseded - new comments belong in the latest thread.
The second thread has now also exceeded 500 comments, so after 42 chapters of MoR it's time for a new thread.
From the first thread: