How big is a 8x10 paper?
You know how is the normal print paper, don't you ? the size of the print paper is 8.5*11, then you can image the 8*10 is a little smaller than that. I hope you can figure that out.
Printing out photos from your computer is like printing out most other things, except you need inkjet photo paper (which you can get at www.continentalphoto.com) and you'll have to feed the paper manually. If you think your printer settings might be a bit off, print out the photo on a regular sheet of 8x10 to make sure the dimensions are right.