It's good to be prepared and know what to look out for. It also makes you crazy and paranoid lol. There is a lot of good information on this site and different answers. Like the saying goes "there's 100 ways to skin a cat". Meaning, this isn't an exact science. The same thing isn't done to every single rabbit with the same perfect result, because rabbits are different sizes and different breads and they all respond differently to surgery, medication, etc. so just know the basics.
1. Provide warm clean cage after surgery
2. Keep them in cage for as long as the vet suggests. 1-2weeks more than likely. No jumping on things in cage.
3. Make sure they are eating, drinking, pooping. May take some time right after surgery so don't panic. Ask the vet when you should get worried if they aren't eating/pooping.
4. Look at stitches daily to make sure it doesn't look infected (red, swollen, pus, drainage).
5. When in doubt... call the vet if you have questions or concerns.