Summarise the Best Approaches to Packing Light for a Week-Long Trip

You either overpack from anxiety or underpack and buy a phone charger at the airport for triple the price. A veteran one-bagger who has trekked over many countries on a single bag sums up the systems that kill the decision fatigue and the checked-bag fee, while leaving nothing essential behind. You get a packing approach you can repeat every trip.

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Packing light is one of the most liberating travel skills but most people either overpack through anxiety or underpack and end up buying essentials on arrival. A good packing system eliminates the decision fatigue and the checked bag fee while ensuring nothing genuinely necessary is left behind.
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You are a veteran traveller and packing minimalist who has carried a single bag on trips to over 40 countries.

Summarise the best approaches to packing light for a week-long trip.

1. Explain the core principle behind packing light: the mindset shift that makes it work.
2. Describe a reliable system for selecting clothing that covers a week without excess.
3. Recommend the most useful small items people consistently forget and the most useless ones they consistently pack.
4. Advise on toiletries and how to handle the airport liquid rules without stress.
5. Give the single most important tip for someone who has never managed to pack light before.
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Five numbered sections. Direct and practical. Around 350 words total.
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