Go to the Видео Tab on your Профиль или on the Fanclub that Ты joined или wanted to contribute to. Now scan toward the corner of the tab and Ты will see something that looks like "+ Add Video". Click on that and add the Ссылка and all other information that is asked for and Ты are set to go.
Tips:
1. There are many sites that have videos. YouTube, Dailymotion, etc. Just find the one that has the video Ты want.