How can I change a models orientation only once

[jjadtru (Jad)]

I would like to change the origin orientation of a model only once.

For example I would use a while loop

local model =  script.Parent

while true do
	--Change the origin orientation of the model once
end

[parslmonious]

You cannot change the origin orientation by assigning it a value.
Use PVInstance:PivotTo().

local model = script.Parent

-- Get the current pivot
local pivot = model:GetPivot()

-- Move the model forward 5 studs in the X direction
model:PivotTo(pivot * CFrame.new(5, 0, 0))

-- Move the model backward 5 studs in the Z direction
local pivot = model:GetPivot()
model:PivotTo(pivot * CFrame.new(0, 0, -5))

-- Rotate the model 90 degrees in the Y axis
-- Move the model backward 5 studs in the Z direction
local pivot = model:GetPivot()
model:PivotTo(pivot * CFrame.Angles(0, math.deg(90), 0))

You might also want to look at Understanding CFrame.