Luggage and bags Mark all of your bags with ID tags. Tie a ribbon around your luggage so you can ID them when you arrive. The AP is a jungle and this will make it easier for you.
Clothing/Shoes/Weather Gear Don't expect to go to the country side and see tulpis if you go in the summer. Plan your trip for sping. Although Europe can be cooler than the US take some light clothes as well it can be hot. Take good walking shoes you will be doing a lot of this.
Toiletries and Medical Supplies If you are picky and you only want to use your brand make sure you take them. These products are not so easy to find and if you do they are costly. Take convertors!
Miscellaneous Pack light espeically if you are heading to other countries and taking the train.
Also bicycles are the main mode of transportation in AMS you have to watch them they do not watch you.
Luggage and bags Holland runs on 220 volts of electricity (North America uses 110 volts). So you'll need to take with you a small voltage transformer (now available in drug and appliance stores or by mail order) that plugs into the round-holed European electrical outlet and converts the Dutch voltage from 220V down to 110V for any small appliance up to 1,500 watts. Don't try to plug an American appliance directly into a European outlet without a transformer; you may ruin your appliance and possibly even start a fire.
Miscellaneous However, some American appliances (such as some electric shavers) are engineered to operate on either 110V or 220V, but even with these you'll usually need to buy a plug adapter.