Traveling is so rough on your skin, but you also can't exactly do a 12-step routine on a moving train in coach.
Instead, I bring some basics: Sephora Charcoal exfoliating wipes, Beia daily hydration and setting mist, Origins GinZing moisturizer, Biossance Squalene and Vitamin C rose oil, and my Fresh Sugar Blood Orange hydrating lip balm.
A lot of my products were free samples since I frequently buy things from Sephora, which save way more space (and are less expensive, being free and all) than travel-sized items.
I also like to bring a Moroccan oil hydrating treatment, flexi rods, and a satin bonnet so I wake up with bouncy curls instead of a tangled and dry mess.