Vesta Structure Modeling with ATAT

Everyone,

I want to start off by saying that I am completely new to all of this, I took a class in which my professor helped me create an alloy structure of GeSn 0%Sn, 3%Sn, 10%Sn, etc. He was able to randomize the location of the tin atoms by using ATAT. I am attempting to recreate what he did, I have asked him for help but I believe he is busy with more important things at this moment. I was wondering do any of you know how to utilize ATAT to randomize the location of tin atoms in a GeSn alloy, and if so can you please give me some guidance either on here or via zoom. Please and thanks.