How Do 你 Make Tribute Videos?

I have seen pretty amazing tribute 视频 for TPoM on youtobe and I have been wanting to make them myself. The only problem is I don't know how to get the 视频 from the episodes and I also would like to know the best softwares (or whatever they are called) to make the 视频 on. If 你 could help then that would be great, thanks! :)