Most hotels provide shower gel, shampoo and conditioner, but it's worth bringing along a facial cleanser that suits your skin type. (And if you find a cleanser that doubles as a mask, so much the better! Extra care for your skin without extra products, meaning more room for souvenirs!)
Keep a little bottle in your bag. If your face feels really disgusting while you're out sightseeing, soak a cotton pad or couple of tissues with toner and give it a quick swipe. It's also an emergency cleansing option at the end of a really exhausting day - just don't make it a habit.
Your skin can become really dry while you're travelling, both from flying and from the unfamiliar climate. Make sure you pack a hydrating lotion without SPF and use it after cleansing.
Wherever you're going on holiday it's important to continue to protect your skin. Whether it's to the beaches of Thailand or the snowy mountains of Japan, wear SPF during the day. (UV rays reflect off the water and snow, so don't think you're safe just because you're wearing a hat!) Choose a waterproof formula that is suitable for both face and body to save space.
Don't forget that your lips need protection from sun damage and dryness, too! There are plenty of lip balms with SPF, while others come with a tint of colour to brighten your smile in those family pics. A creamy formula like a lip crayon will give you lasting colour, and can also double up as a cheek stain.
We all know you need to reapply sun screen during the day, but just in case you forget or missed a spot, it's good to have aloe-rich after-sun gel handy to soothe those burns. Ouch!
Come home with snapshots and souvenirs, not mosquito bites. Sprays work well, as do patches. Anti-mosquito wristbands are funky and usually last several days. There are some that are covered in cloth, so your skin doesn't come into contact with the actual substance, so you won't suffer allergic reactions. Some are even waterproof!