Mine was done outpatient, but I had to stay near my surgeon's office overnight so that she could look me over in the morning. To surgery, I wore a pair of basketball shorts, underwear, slip on shoes, and a button up shirt. In my overnight bag for the hotel, I packed a change of underwear and socks and a pillow.
We brought all my prescription meds that my surgeon told me to get (anti-anxiety, sleep, anti-nausea, and pain meds). We also got ginger ale and crackers. When it was clear that I was fine to eat real food (probably 5ish hours post-op), I had a friend come over and bring me some soup and lemonade.
Phone charger, phone, wallet, keys. I think that's about it.