I had two emergency CS with my two DC.
I'm a size 18 (normally, when not pregnant), and found Tesco "Full Briefs" aka granny knickers, very generous and came up very high over the belly, totally missing the scar, even with a giant maternity pad. Really, don't go the paper knicker route. Cheap cotton knickers are not much more than buying disposables, and I never needed to throw any away, just blitzed them in the wash!
Remember something nice and loose and fitting above the scar for going home in too.
Ask the consultant if they can swab out as much blood as possible during the op - they didn't at Cheltenham, and there was a big gush when I stood up which was a bit horrible (happened for all the CS girls on the ward!!!). At Warwick they did swab it out, and it was much more manageable!
I had skin to skin while being stitched - tell them if you want this in case they aren't progressive, or don't realise you want it.
Talk to the consultant about pain relief - at Cheltenham I had codeine. I was in agony. At Warwick, they gave oral morphine and I had so little pain, I was out of recovery at 1pm, walking down to the day room to make tea at 10pm. I was a bit worried about morphine, but honestly it didn't have any noticeable effect except the pain relief. Had lunch right after recovery as I was starving and felt loads better! (Had a light salad). Ask for help if you are in pain - don't be brave!!!
To change the baby's nappies, I used my electric bed to lift the baby so I didn't need to bend.
I showered next day - and OMG how much better does that make you feel!! I used tea tree shower gel (you can get this from Holland and Barratt) as I was completely paranoid about infections! I was told this can put babies off BF, but DD1 didn't BF, DD2 did - I don't think it made a difference.
Don't fear the scar. I had to take off my dressing in the shower both times. The water make it easier to take off. I just kind of didn't look, as I'm very squeamish! They cut through your nerves during the op, so just pat it very gently dry after washing and you will hardly feel a thing! After a couple of months the scar is nothing major, after a year it is just a faint silver line.
If you feel too poorly to get out of bed to get your baby etc, don't feel bad about ringing the bell for the midwife, even if you have to keep doing it. I found a kind of roll onto my side, and push up, then lower the bed made getting up more manageable.
Good luck! I'm sure you'll do fine.