adding contrast in photoshop

I have not worked with these programs at all before this year so I am having to look up simple things like adding contrast. The quality of my photographic study pictures was decent in color but in the black and white print out I was having trouble with how they all read at about the same gray tone. Here is one website I found with some lengthy instructions on adding contrast to a photo. There are many steps to his process which may not all be necessary but it helped me to learn about more functions and buttons in photoshop. http://www.photoshopessentials.com/photo-effects/extreme-contrast/