This article is great information:
http://www.bio.miami.edu/hare/opcare.html
This is more good info and a list of questions to ask a vet:
https://rabbit.org/health/spay.html
I wish I had scheduled an appointment with several different vets and asked them some probing questions about their surgery protocol (do they intubate, how do they keep the rabbit warm, what pain management, etc). It would have been worth the money, as it turned out the vet I went to did not have as much experience as he led me to believe. For instance, when I picked her up, he said he'd had trouble finding her uterus, and when my bunny didn't eat or drink for 24 hours afterward, he said not to worry about it as they can go 48 hours without eating (wrong).
The most crucial thing in my experience is
warmth during and after surgery to maintain body temperature (especially for smaller or skinnier buns), and
pain meds (usually meloxicam). Take a Snugglesafe or heating pad with when you pick her up to keep her warm on the way home, or some fleece to wrap her in. I gave mine a heating pad at home and she spent hours on it. A warm, quiet room is good.
Being incapacitated by surgery can be stressful on a prey animal because they feel they can't run away or defend themselves, so it's also good if you can be nearby so she can feel safe.
By the way, I tried to tempt her to eat with tons of foods, and finally got her to start eating with a piece of orange! The only bunny I ever had that liked oranges. Alfalfa hay works for a lot of bunnies.
I also found out later that meloxicam was likely to cause this particular bunny to stop eating, so be aware that not eating can be because of the surgery or because of pain med's effects on the stomach. I always give it with food so that it is less likely to upset their tummy.