Mystified by how many ounces of liquids toiletries to take on a trip? I use this measure: 2 oz of shampoo and 1 oz of conditioner per week. I measure every other liquid by how much I use compared to that. Body lotion? 2 oz. Facial creme? .25 oz. And so on. I purchase mini bottles and containers and keep them in a container full of travel items and baggies.