Walking Alone, Amsterdam
Keep some extra change in your pocket in case somebody holds you up ! ( try to mug you )
Don't keep to much money on you - and do not walk alone in nighttime. espescially aroung the train station and in the downtown areas. Don't fall into the canals - their toxic and bad for your health ! :)
Chances of getting mugged if not careful - stay sober , and never alone !
Any bike has a potential of being stolen - Stay away from the bikers - otherwise you migh be run down !
Don't take any major chances
I will start by saying Amsterdam is not that hard to find your way around and there always seems to be someone to help you out but I still got lost a number of times and ran into some more travelers who did the same, why? well lets just blame it on the coffe shops that that this great city is so famous for.
After a long night out, negotiating steep, slippery slate steps is more difficult than trying to say that outloud....
Make sure you're well enough to make it home!