Cook the orzo pasta according to the packet's instructions. Drain, let cool for a few minutes, place in a bowl, and mix with the olive oil.
Deseed and chop the cucumber. Add to the pasta bowl together with the herbs, feta, and lemon zest. Add lemon juice to taste and keep what is left, you might want to add some more of it to the salad just before serving.
Add salt and pepper to taste, cover the bowl with plastic foil, and place in the fridge for a couple of hours.
Just before serving adjust the taste again with some more lemon juice, salt, and pepper. I find the salad tasted even better the next day.