I can help, my friend and I practiced this once.
1; Shadows are your friend
2; Don't walk like a spy in the movies half crouched with your arms spread out wide. Walk normally but slowly.
3; Wear all black clothing
4; If you think someone has spotted you, don't just run around. Stand still god damnit. In the dark your eyes play tricks on you, or so people think.
5; Blending in with objects is a great way not to be spotted. My friend once hid behind a street light for a solid 15 minutes before I noticed him.
6; Crossing streets, a big nono. There is lights all over the street. Even if you cross in a shadow the light behind you will give you away.
7; Just because your out in the open, doesn't mean your screwed.
Another tip, do you have any black sheets? Try to fashion one into a robe with a hood, it will break up your outline and make you harder to spot.
And remember, your not a ninja, your white.