Ralph's tutorial is very comprehensive and should help enormously.
The monitor calibration is key, the visual equivalent to musicians tuning their instruments. Thus with your calibrated monitor, you are able to adjust the scanner software and possible subsequent tweak in Photoshop (or equivalent) so that the image on your screen matches the original print. Then everyone else who has a calibrated monitor will also share your original vision, crafted in the dark room. A setting of 5000K with gamma of 2.2 (PC or Mac) is now regarded as the standard for print viewing.