Personally, I can't see the point of destroying a habitat that exists, in order to create an artificial 'wild' habitat. On TV, a few months ago we did see a wildflower meadow, that was rotovated every year. To me, that makes for a lot of work, and little sense.
Seeds sown directly into grass will go nowhere. So you would need to germinate them in modules, and raise some little plants. You could then plant them in the grass. But wild flowers will struggle to survive against vigourous grasses. It might be feasible to pull grass away from around the plants, periodically.
You could dig over a very small area, and sow some seeds into soil. But germination will not be as good as with seed sown in modules, and you'll still have to deal with the grass when that grows.
A long term solution is to weaken grass, which you can do by cutting it yearly, and removing all the clippings. That's what haymaking does, and that produces a wildflower meadow, quite naturally.