I had a great recovery from my ELCS and was able to sleep any way I wanted from the start, it wasn't a problem at all to sleep on my side. I sometimes co slept in the hospital but that was by choice because of exhaustion from constant breastfeeding, rather than any physical issues.
For the first 12 hours post op I was attached to drips and urinary catheter etc so couldn't get up until they were removed and epidural worn off. The midwives helped with baby at that point. But as soon as they were out, about 12 hours post op, I was able to get out of bed, shuffle around, lift baby etc. Don't be afraid to use the call bell if you do need help though!
I was slow and moving gingerly at the start, but felt a LOT more mobile than I did being heavily pregnant!!
You mainly have to be careful while sitting up/ getting out of bed - so instead of sitting straight up from lying, you roll onto your side and swing your legs out, and use your arms to help pull your upper half up.
I've heard of some people looping a scarf around the bottom of the bed and using that to pull themselves up either, and having a litter picker type gadget to pick up things that have fallen, I didn't bother with either of those though and was fine.
I could get up from the couch fine but I know some people use a few cushions under them, or sit on a kitchen chair for the first few days, as it's a bit easier to get up if you're sitting higher.
I wasn't in pain at all but I was advised to keep taking my pain relief without a break, and I did. And I also got mobile as quickly as possible post op - just shuffled a few steps around the room at first - no marathons or anything!
The dressing I had was fully waterproof/showerproof so no issues there.
Consider whatever steps you can take to get help at home post op - whether from your partner, family, or paid help like cleaners/ getting meals in. Just try to make provision to have the first 2 weeks as easy as possible. Don't be worrying about the house being tidy etc, just go easy on yourself as you would after any major surgery!
Altogether I found the ELCS a lovely way to have a baby. I will do it again next time with no hesitation. Very best of luck with it OP!