[tutanchamun]

Maybe you can rent a sod remover machine? I've seen those rented out for ~40 USD per day.

https://www.youtube.com/watch?v=B8Qd33NhflQ

With those machines it's more comfortable then the spade method [0], especially if the area is larger. After the sod is removed (you can put it on the compost with the bottom up to regain good soil for future uses) pour sand onto the area and mix it in. This will remove nutrients from the soil which is what many wildflowers like.

Then throw out your wildflower seeds which you need to press on afterwards (there are tools, but as a cheap method you can just walk over them), so that the wind doesn't blow them away. In the end water them (also for the next 2-4 weeks).

[0] https://www.youtube.com/watch?v=VQuffl5Engo