If you want your instructions to be even more realistic you can download the new configuration file LDConfig.ldr and place in the root folder of your LDraw installation. Here is what Scott Wardlaw wrote on LUGNET:
By popular request, some of the original color values have been updated to colors more representative of the real bricks.
Official download site: http://www.ldraw.org/library/official/LDConfig.ldr.
Also, LDCfgalt.ldr has been updated with equal color values as LDConfig, but edge values are set to be more representative of the real bricks.
Official download site: http://www.ldraw.org/library/official/LDCfgalt.ldr.
If you have any comments or problems please consult the resources below or ask in the FAQ on this site.
For more information see http://news.lugnet.com/cad/?n=17777 and/or http://www.flickr.com/groups/ldraw/