Our outside space was pretty open plan when we moved in. That's because the previous owners had never owned an animal on it in their 27 years of living on it. It was a larger farm when they owned it too, it was split and sold off (subsequently making them millionaires, so I am guessing they knew that on day 1). Anyway, I digress.
So when we moved in, to keep animals where they are supposed to be, we started putting fences up and where we needed gates, we used temporary measures.