Are you traveling overseas or domestic?
For overnight domestic I usually do the following on the plane:
Magazine or book for when you have to turn your electronic devices off.
Headphones so you can listen to music or watch a movie.
A bottle of water and a larabar. Airport food is generaly crappy
Tech: iPhone charger, MiFi and charger, laptop and charger
I usually use this bag – it has travelled around the world with me for work trips (although mine is black, not sure about this color)
In my overnight bag (small roller bag for a few days, I always take a pashmina (it has saved me from freezing in client cube farms so many times). IF it’s the summer and I’m not wearing a coat I pull it out and wear it on the plane.
A few extra larabars as snacks, maybe nuts as well
Travel size toiletries e.g. shampoo, conditioner, toothpaste and toothbrush, smaller hair brush
2 shades of lipstick, eyeliner, mascara
Dresses that won’t wrinkle & a cardigan or leather jacket
Accessories to make it interesting – e.g. a scarf or necklace
Heels and flat shoes
Gym gear depending on how long I am gone for and hotel facilities (the funniest was when I was in a Japanese gym and the treadmill showed that I burned a bowl of rice and a banana.)
Depending on the hotel and the length of the trip I might bring slippers or even a small bathrobe – little things make a big difference! Obviously if you are only gone for a night or two it’s no biggie but I find I often have only 1 or two meetings/day so I will spend the morning working in my hotel.