First, start by copying the embed code underneath the YouTube video's pane.
Now, after placing it in your profile's editor, erase everything in the code that comes before " < embed > " and after " < / embed > " . Next, click inside the url in the code, which is in quotation marks, & between the last character of the url & the closing quotation, type
&autoplay=1
That will make it play automatically :)
so enjoy and forget to click play...:))))