Many trips have one or two forgotten items that produce significant inconvenience or expense — phone charger, contact lenses, specific medication, important document. A written 'don't forget' list used for every trip prevents this.
What to include
Documents (passport, insurance, tickets). Medications (with prescription documentation). Electronics (chargers, adapters, devices). Health items (contact lenses, glasses, toiletries). Trip-specific items (swimwear, ski gear, formal wear).
Where to keep
Notes app, printed copy, or Google Docs. Reviewed 24 hours before departure.
Most travellers benefit. The compounded peace of mind across years of travel makes it worthwhile.