I'm trying to make a viewmodel but i don't know how to rotate it properly?

So I'm trying to make a ViewModel but I don't know how to rotate it, i use this:

    RunService:BindToRenderStep("ViewModel",Enum.RenderPriority.Camera.Value+1,function()

        ViewModel.CFrame = Camera.CFrame* CFrame.new(Vector3.new(0,0,-3),Vector3.new(0,0,0))

    end)

whenever i try to use the second vector3 in the CFrame it just confuses me and it wont work, i understand eualar angles but i cant get it to work properly.