How to leave my shutter open on my Nikon D3000?

I want to get that cool trailing effect from lights. I want to get into night life photography for spotting at raves and clubs. I really don't know much about my d3000 at all. Just got it about a week ago although I have been reading alot. Does anyone know how to get the shutter effect?
And if you have any good tips on night life photography it would be more than appreciated.

Added (1). Or I guess it is also called a long exposure.

The best thing to do is to sit down with your manual and try each function, this will enable you to understand each effect and how to obtain it.

Your camera has a shutter speed range of from 30 seconds to 1/4000 sec. To use the longer shutter speeds you'll need to be in Manual Mode so look in your Owner's Manual and find out how to access Manual Mode. The D3000 also has a Bulb mode which allows you to hold the shutter open as long as you want but a 30 second exposure will be more than sufficient for light trails.

30 seconds is a long exposure and will require the use of a tripod. You can use the camera's self-timer to release the shutter so learn how to access that feature. When using your camera and 18-55mm zoom on a tripod, turn the VR on the lens to OFF.

I use and recommend this site for night exposures: http://www.calculator.org/...osure.aspx I chose the Scene 'Distant view of city skyline or floodlit buildings' and ISO 200 for these:
100mm lens at f11, exposure of 30 seconds.
200mm lens at f11, exposure of 30 seconds.

These pictures would have been impossible to take without a tripod. You'll also need a tripod for your light trails so add a tripod to your list of things to buy.

Shooting in clubs is a whole different set of problems. Trying to use the 18-55mm f3.5-5.6 zoom that came with the camera will require using a very high ISO or an external flash unit. If you'll refer to the previously referenced Exposure calculator and choose the Scene 'Domestic interiors at night, subject lit by campfire or bonfire' and choose ISO 800 and then look at the chart of f-stop/shutter speed combinations you'll quickly understand why a fast lens like the Nikon AF-S 50mm f1.4 is desirable.

ISO 800
f1.4 @ 1/125 sec.
f2.0 @ 1/60 sec.
f2.8 @ 1/30 sec.
*** f3.5 @ ~ 1/20 sec. *** This is your 18-55mm f3.5-5.6 zoom at 18mm wide-open.
f4.0 @ 1/15 sec.
*** f5.6 @ 1/8 sec. *** This is your 18-55mm f3.5-5.6 zoom at 55mm wide-open.
If you double the ISO to 1600 the above shutter speeds will also double. With the VR ON you might be able to get usable results at f3.5 @ ~ 1/40 sec. But even the least subject movement will be blurred.
NOTE: All of the above is based on what amounts to an average living room at night. A club will be much darker and require an even higher ISO even with a 50mm f1.4 lens.

A DSLR is not some magical device that allows you to ignore the need for sufficient light in order to make a picture. Using a slow lens like the 18-55mm f3.5-5.6 compounds the problem although the ability to increase the ISO at will helps but its a trade-off - higher ISO means increased digital noise.

With an external flash like the Nikon SB-600 AF Speedlight you can use a much lower ISO and your 18-55mm zoom. Since even off-camera direct flash can be harsh you might consider adding the Gary Fong Lightsphere to your flash unit.
http://www.garyfongestore.com/lightsphere-collapsible-370.html You can buy it cheaper at B&H:
http://www.bhphotovideo.com/...ovideo.com B&H is also a good source for the SB-600 Speedlight and the AF-S 50mm f1.4 lens should you choose to purchase them.

If your only choice is to use a high ISO then you'll have to deal with the resultant digital noise. Check in your Owner's Manual for Nikon's suggestions on how to do this and then read this article:
http://www.shutterbug.net/equipmentreviews/software_computers/0309noise/index.html

Another technique you can use in low-light situations is to switch to Spot Metering which meters a 3.5mm circle centered on the active focus area. By using Spot Metering you'll only be metering for your subject, not the subject and its surroundings. This should result in a marginally faster shutter speed but the background will probably be black or at the very least heavily underexposed. Again, at slower shutter speeds any subject movement will be recorded as a blur.

Good luck and have fun learning more about your camera and photography.