During your journey you're likely to experience a range of weather conditions. You should avoid choosing an outfit for only hot weather or only cold weather. Instead, opt for comfortable and safe clothing with several layers of varying thickness that you can take off or put on depending on the weather.
Your priority should be to choose equipment that will keep you safe on your bike: legs, shins, knees, hips, back, shoulders, elbows, fingers, head and eyes. Then opt for base layers made from natural fibres so the skin can breathe (woollen socks, cotton underwear and T-shirts).
Avoid wearing jeans or thick woollen jumpers. Make the most of specialist clothing such as a fleece for wearing over T-shirts, motorcycle trousers and a good jacket that should be watertight, windproof and protect against insects while still allowing the skin to breathe. When it comes to your boots, helmet and gloves, don't compromise on safety and make sure you choose the right equipment for your bike.
You might also decide to invest in a camel bag for easy hydration, a rain cover for heavy downpours and an intercom system to talk with your passenger.