Use this list as a reference while shopping and packing for your Scotland trip so you don't forget anything.
A good, high-quality pair of hiking boots is arguably your most important piece of gear. They should be comfortable and durable while keeping your feet warm and dry and providing ankle support. For this purpose, leather boots may be the best option as they're sturdy, waterproof and warm. While pricey, they're worth investing in as they should last you for a long time. No matter what kind of boots you choose, make sure to break them in before your trip.
Equally important as your boots are socks. Cotton socks cause friction, potentially leading to blisters. Instead, opt for wool socks made from Merino wool which is lightweight, anti-itch, insulated, and can wick moisture.
Along with your synthetic or Merino base layer, you'll want a good mix of long sleeves, T-shirts and pullover jackets like fleeces for the upper body. On top of it all, add a shell jacket that's breathable and waterproof.
For women, a sports bra may also provide better support when hiking.