I think it’s personal preference. I was in for two nights and stayed in my hospital gown and then nightie, but I did see another lady who had changed in outside clothes the next day. I don’t think you’d want to change too soon though, as you might find it quite uncomfortable.
I’ve had two sections and I didn’t use a binder for either. The key in the first few weeks is to air the wound as much as possible and keep it completely dry, and I don’t think a binder would work with that. I wore mesh disposable pants and dresses for as much air as possible. I used water only on the wound in the shower (as advised by the midwife), dried it with a clean maternity pad, and then lay on the bed for 5 minutes to air it. Both times my scar healed extremely well.
The midwives will tell you this as well, but try to move around gently, as much as pain permits, and as soon as you can. The nurses got me out of bed 4 hours after the second section, and I found the recovery the easiest. Do listen to your body though, and don’t bend, lift, or make sudden movements.
Do keep on top of your pain relief religiously. Absolutely do ask for more pain relief in hospital if you need it and don’t let anyone fob you off. You should not be in pain (as the anaesthetist told me). I had oramorph the first day for the second section (the first two days for the first section) then Codydramol and ibuprofen for a full week afterwards. I stayed on ibuprofen and paracetamol for a good while after, until I didn’t need them. I had a very smooth and easy recovery both times.
A pillow between the wound and the seat belt is a godsend in the car on the way home.
And whatever you do, do not put tea tree oil anywhere near the wound. There was a craze for that on the internet a few years ago, but it dissolves the stitches. A doctor warned me at discharge!