Hello! As a native English speaker, this is not a phrase I am familiar with. It might be an idiom that I have not heard before, but it's not a common expression. I would guess that it means to stop being like everyone else, to stop conforming. Where did you hear this phrase?

It's definitely not a common expression and it's very difficult to say what it means out of context. To "smash" something, means to crush, or destroy something. "Sameness" means that things are the same, identical. So to "smash the sameness" could mean that you don't want things to be the same (generally meaning "boring"). However, you'll have to give the context for us to really be able to help you with this.

Google "smash the sameness" ==> 3 hits as a comparison, I made up a new phrase "ride the lion" Google "ride the lion" ==> 879,000 hits. . I think we can conclude that "smash the sameness" is not a common expression. . I guess that means that you can use it any way you'd like to. It'll mean "be different" to most people. . ... http://www.smearmagazine.com/posts/2016/10/25/smashing-the-sameness Furthermore, their ploys at gaining customers smash the sameness that threatens . It appears to be a page of images of things a little different to usual. . Maybe something like Let's smash the sameness and have icecream first.