There's multiple things going on there. What we see in the youtube link above is not what the user sees - she has additional video editing to show her monitors video output within the single youtube video. She plays across multiple monitors, her main on 1 monitor and her 9 alts on a 2nd montitor. In terms of "how do I do that?" Its really not 1 thing, there's probably multiple pieces of software, multiple pieces of hardware. At the core, she's using her own developed application, similar to ISBoxer & Innerspace, but I don't know enough to say if she forked off the current development recently or maybe its completely different, just with a similar UI. Check out her youtube channel and go back a ways for older videos where she talks about her setup. She hasn't really explicitly said what pieces shed updated since the software broadcast ban went into effect, but she says that she's doing it in hardware now.

If you have a specific part of her screen, or a specific function you have a question about how she does 1 action, we can try to dig into that some more.