Baby steps is key for me. I can build very ambitious things but I never ask it to do too much at once. Focus a lot on having it get the docs right before it writes any code (it'll use the docs) make the instructions reflexive (i.e. "update the docs when done"). Make libraries, composable parts... I don't want to be condescending since you may have tried all of that, but I feel like I'm treating it the same as when I architect things for large teams, thinking in layers and little pieces that can be assembled to achieve what I want.

I'll add that it does require some banging your head against the wall at times. I normally will only test the code after doing a bunch of this stuff. It often doesn't work as I want at that point and I'll spend a day "begging" it to fix all of the problems. I've always been able to get over those hurdles, and I have it think about why it failed and try to bake the reasoning into the docs/tests... to avoid that in the future.

I did make lots of design documents and sub-demos. I think I could have been cleverer about finding smaller pieces of the project which could be deliverables in themselves and which the later project could depend on as imported libraries.