Choose your luggage carefully. Something that can be easily managed, carried for long periods of time and left conveniently in the bus is ideal. A large backpack or rolling suitcase should be quite sufficient.
Firm up your destinations and dates. Knowing what cities you will be stopping in and the seasonal dates will be crucial when choosing how heavy or lightweight your clothes should be. Check the average temperatures for the dates you will be there.
Pack two T-shirts and two pairs of comfortable trousers to start. Vary the thickness of each so you will have clothing for different weather and the option to layer. Choose materials that dry quickly.
Fill out your clothing with collared, wrinkle-proof shirts and tops and skirts or dressy slacks (as applicable). You will find yourself blending in more with Europeans when you are outside the bus if you don't stick with the most casual T-shirts and jeans.
Add a raincoat or light coat, umbrella, long underwear, a sweater and a scarf or two for cold nights or adverse weather.
Find a pair of comfortable walking shoes and sandals. If you plan on a few formal outings, pack a pair of "good" shoes. These should get you through the trip and not take up too much space.
Pack undergarments, socks, tights and toiletries based on how much travel-time you will have between hotel or hostel stays. If your bus journeys do not cover long distances, you will want to pack lightly in this area, as you will have plenty of opportunities to buy toiletries and wash your undergarments and hosiery.
Keep personal items like books and MP3 players handy during your travel time in the bus. Store your digital camera close by to capture places en route to your destination.
Get a power adapter that can convert plugs all over Europe. While continental Europe uses two-pronged plugs, Great Britain uses large three-pronged plugs, so you will want to prepare to use both types of outlets. Often outlets are available in long-distance buses.
Pack a travel clock, writing materials, sunglasses, tissues and a rechargeable phone card.
