You have checked the forecast. Sunny, eighteen degrees, light breeze. Wonderful. By 2pm you are sheltering under a bus stop in horizontal rain wondering where it all went wrong. The trick is layers. Always layers. A t-shirt, a long sleeve, a fleece or jumper, and a properly waterproof jacket. Not 'shower resistant'. Waterproof. There is a difference and you will learn it the hard way. Footwear matters. Trainers are fine in town. The moment you set foot on a footpath, a coastal path or anything described as 'rugged', you will want proper boots. Wet socks are the enemy of joy. Always carry: a small umbrella, a packet of tissues, a chocolate bar for emergencies, and a tote bag for the inevitable charity shop detour. Never carry: an umbrella the size of a small marquee, white trainers, or anything dry-clean-only. This is Britain. Plan accordingly.