What settings do I need to achieve a good (blue) contrasting Infrared Photo (Nikon d90)?

I'm quite aware that 20 secs to 45 secs is required to have a good picture if you're gonna use Nikon d90. BUT I want to know how I can achieve a Blue light with dark contrasting clouds.btw I'm using a IR Haida 67mm 720. Thanks. I'm getting a red clouds. I prefer blue

The blueish infrared pics you see on the web are either the result of using a near-infrared filter somewhere in the 620-660 nm range, or (extensive) digital post-processing, using for instance, photoshop.
The effect also very much depends on the infrared sensitivity and in-camera processing of the equipment that's being used.

In colour mode, your D90 will record part of the (near-)infrared spectrum because of the filter. Essentially, you'll need to convert the resulting colour pic into its separate colour channels and apply a few toning processes to get the effect you want. The result is a so-called false infrared image, a term that originates from the infrared colour film era, when (kodak) infrared slide film was used to 'translate' shades of infrared into different colours within the visible spectrum. For more info, see links below.

Having said that, the (excellent) D90's anti-alias filter in front of the sensor makes your camera a lot less sensitive to infrared than some earlier Nikon models in order to reduce moire: jagged edge contrast transitions - which generally speaking is a good thing. I use an old D100 which I picked up for peanuts for infrared shots because its sensor is far more infrared sensitive.
And if your really serious about infrared, you can have your camera converted to IR-only, i.e. Have the anti-alias filter removed.

You need to process the images to make them look like that.

Here's a tutorial.http://www.shotaddict.com/tips/article_How+To+Post+Process+Your+Infrared+Digital+Photos.html

They use Adobe Photoshop, but it could also be done in GIMP which is free http://www.gimp.org/...w.gimp.org

You have to do color channel swapping, setting the red channel to cyan and the cyan channel to red…
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This is the short simple version…
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The long drawn out version will require YOU to do some reading up on the subject and experiment, a LOT.
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Also, don't forget to re-set your Custom White Light balance too. Often it is not kept on - white!
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Your D-90 has a IR blocking filter over your chip that sees. Don't expect work to come out like images seen with cameras that have this filter removed, even with long exposures (but even when using a 87c filter which is virtually black, I never had exposures THAT long). Noise builds up, grain get very bad and colors shift even worse, but experiment for that is how discoveries are made.
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"Forcing" the camera to see IR is like anything forced. Results are not always very good. By putting a IR filter over your camera's lens and attempting to take a picture, a longer exposure IS needed because you are trying to force IR onto the chip. Oh, it will work, some, but results WILL vary and a lot of experimenting is required. If you have seen it done, READ how THEY did it and copy THEIR techiques…