Kids these days. They've seen it all. You should know by now that a website banner ad indiscriminately shouting “buy my product” from the rooftops is just noise if not out-and-out offensive. Young adults browsing online are actively looking for something, so don’t get in the way. Make your content a genuinely interesting destination rather than an interruption.
To attract the attention of young adults, you must be one or more of the following: genuine, cute, funny, shocking, emotional, provocative, awe-inspiring, gross-out, indie, spontaneous.