I have copied this from another one of my posts in another thread so I hope this helps - I have amended it a little
Phone, headphones and charger
Toothbrush, toothpaste, mouthwash
Gum - not sure about this one as yet
Eyemask and ear plugs
Wet toilet wipes
Pads (someone has mentioned that your period can start after surgery)
Will wear same clothes home as I wore to hospital
Jumper/dressing gown - the dressing gown could double as a blanket, but if you are cold, the hospital will offer more blankets
Shawl - acts like a light jacket around arms if needed
Pillow - my absolute must have
Heat Pack - Hoteeze - this is a stick on heat pad that stays hot for up to 8 hours and helps relieve the shoulder tip pain I hear
Pen and paper
Slippers and socks - but I think I will just do my ballet flats
This is a working list in progress - I keep thinking of the fact I have to pack all this up when I am going to be in a lot of pain, so I may cut a heap out still.
Some people have mentioned they take their iPads and stuff to read, but others are saying you really won't feel like reading much at all. I'm probably going to load my phone with things to watch (I have the iPhone 6s Plus so it is quite a big screen) rather than read.
Hope this helps!