What kind of camera do you have? Is it a DSLR? If so I can tell you. Otherwise, it should have a 'night' mode.
Basically...you need to set your shutter speed to a really slow one (like 2" +- - it's usually probably like 1/10-1/1000 on most cameras) and keep the camera SUPER steady. Shaking will result in a very blurry image as the shutter is open that long and captures every movement. Also, to combat this you can set the shutter to a faster speed (like 1") but turn the ISO setting up. I shoot everything on ISO 100 because it's the least graniest, but if you change it to like ISO 800, your picture will be brighter...thus allowing you to make the shutter faster because you don't need to capture so much light.
Hope you understood all that lol.