An image program is one that allows you to manipulate images. If you've never done it, the easiest thing to do is to just go to the place on your computer where you just saved the image and double click it. It will open in your system's default image editor. Most of the time, this isn't a very good one. After the image is opened, it must be 'formatted' or 'sized' to print.
All image editing programs are slightly different.
Yours may or may not automatically print the image in the proper size. If you don't know, all you can do is experiment. Open the image program. Use the image program to open the image that you just saved. If you happen to be using 'Ulead's Photo Impact', then you have reached the final step.