If you get to Switzerland, go to Interlaken. Great place to meet young people, great hiking as well. Have fun, take a photocopy of your passport (main page) and keep it separate from your passport. This will make things easier if you loose your passport. Use your ATM to get cash. This way you can possible get better exchange rates as they change. If you take travelers checks, split them up. Don't keep all of them in your wallet. Watch your back for pickpockets.
Don't worry, the girls in the Red Light District in Amsterdam are clean. They have to get tested regularly
Dave