How to access to AWS EC2 G3 instances simultaneously?

I want to use Nvidia Grid on AWS EC2 g3 windows server instance for multiple user’s simultaneous access. But I don’t know how to use it. I managed to install Nvidia Grid Driver on EC2 g3 windows server instance, but when I access to EC2 via VNC, only one user can access to that vm. No matter where I look at the NVIDIA home page, I can only find that I can use vGPU with nvidia grid, but it does not tell me how to use it.
And I don’t to use Citrix or Vmware because that tools are too heavy.
Please tell me the way I can use nvidia grid on AWS EC2.
Thank you.