The weight limit for a checked bag is 50 pounds.  Consider the weight of your empty suitcase.  Do you have a lighter one?
Shoes add weight to your luggage.  Try to limit yourself to one pair plus your uniform shoes. 
Take your full uniform EXCEPT shako.
Plan to wear clothes (especially jeans) more than once.
Save room in your luggage for small souvenirs.
Review airline regulations for what can be carried on and what must be checked (liquids, metal items, etc.)
Check your portable electronic equipment (iPod, camera, etc.) for dual voltage compatibility.  This will determine whether it requires a transformer or simply an adapter.

The airlines will allow you to bring one checked suitcase, one carry-on, and a personal item (purse or briefcase) free of charge.  Instruments that are small enough should be carried-on.  Larger instruments must be checked.  This will be considered a second checked bag.  There is a $50 charge for a second checked bag.

More information on baggage and equipment

Concert Band Members: Please remember that you must bring your own folding stand.  Bind the two parts together and label it with your name.  We will collect all of the stands on January 3rd and pack them together. 

The cruise ship has both US (120) and EU (220) voltage outlets.
All appliances that produce heat are forbidden on the cruise ship.  This includes hair dryers, curling irons, clothes irons, etc.  There is a ship-approved hair dryer in your room.

There will be three formal nights on the ship.  I would recommend that you take one formal outfit (coat and tie / cocktail dress).  Otherwise you should dress for comfort.  Rome tends to be more fashion conscious than most other cities.  The trend is dark, well fitted clothing.  Jeans are perfectly acceptable in the city but they are never tattered and are generally dressed up with a wool blazer, fitted sweater, or pea coat and dark shoes. 

The weather in most places will be in the 50s during the day and 30s/40s at night.  The top deck on the ship will be VERY windy.  You will not need a heavy coat in any location.

Check the regulations before going ashore at each port to make sure you are dressed appropriately for what you plan to do that day.  These regulations are easy to check on the ship.  Just ask someone.  Here are a few specifics.
    --Women should cover their heads in Islamic holy areas.  This applies to mosques, primarily in Turkey.  It does not apply to public areas.
    --Men should cover their heads in Jewish holy areas.  This applies to Temples, the Western Wall plaza, etc.
    --Shoes must be removed when entering a mosque.
    --No exposed shoulders or knees in the holy areas of ANY religious faith.  Christian, Jewish, or Islam