Top tip, bring as many tampons as possible! They are practically gold dust in Asia.
Choose your clothes wisely. Yes, that outfit would look amazing on your Instagram, but how will it feel walking up a mountain in 30+ degree heat? By all means go for the pretty clothes, just make sure they will actually be comfy.
Before leaving, half what you've packed and then half again. Believe me, all those clothes are not worth carrying on your back!
If your hair also expands to twice the size of your head like mine, embrace it! But if you need to tame the locks from Hagrid to Gigi Hadid, stock up on good de-frizz sprays and cute bandanas.
Remember you will always need the basics. Do not give away/send home clothes because it doesn't suit the weather (E.g. jumpers, trousers) they may not be the most stylish piece of clothing you have but trust me you'll regret it when you land somewhere you expected to be hot but it feels like you landed at the North Pole!