I'm in my first year as a PhD student and I'm trying to learn about twistors. I found the question about the book recommendations for twistor theory, but it quickly became clear that my knowledge of differential geometry is vague at best. I looked at some recommendations for differential geometry, but either they're too basic and don't cover what I need, either they're too advanced and already assume a mountain of dif. geo. knowledge.
So my question is, what are some good books about differential geometry to be able to understand twistor theory?
