Agree with PP re drinking loads. I was majorly thirsty anyway, maternity hospitals are generally really hot, but once the catheter was out they wanted, if I recall correctly, 500ml of urine. I did it in one go cause I'd drank so much! They just gave me a wee cup with a jug which would have been a pain to constantly refill but thankfully I took a big bottle in to use.
I had an EMCS first time and an elective with my second. Second was much calmer because, obviously, it wasn't an emergency. The surgical team were great, it's major surgery but they do it day in day out and kept me calm, even made me laugh. They asked if I minded having music on, it was just something like Smooth FM so 80's/90's cheese, lights were bright for obvious reasons!
I'd recommend trying to get up as soon as possible and moving about as much as possible. Take the drugs they offer and when you get home, take them regularly for at least the next few days - I found I started dropping the amount of paracetamol I needed quite quickly but kept up the diclofenac until it was done.
Massive pants and thick pads(I liked the Boots ones), more than what you think you'll need as you bleed loads and need regular changes and loose, high waisted clothes.
Take lots of snacks to munch on when you're back at your bed - ones you can easily reach and use one hand for. TBH I'd also take some pasta pots or something as hospital food is rank - no way it can be nutritious!
From c.3 months PP I've also been seeing a massage therapist to help my recovery. She is trained in scar work and highly recommends silicon strips to promote healing and reduce keloid scarring. My GP friend also mentioned them to me.
If you plan on Breastfeeding, milk can come in a little later because your body hasn't gone through the full birth experience/hormones so I'd recommend taking a breast pump in with you and doing some additional expressing on top of all the skin to skin and feeding you do. My milk came in by day 3 with number 2 and I out that down to expressing. I tried to express colostrum in advance too but wasn't able to get much out at all.
For home, if you have upstairs, I'd recommend having changing stuff downstairs as well as up, saves having to climb up and down in the early days.
Good luck, its all worth it when you get to snuggle that wee baby!