Its ok if its not getting professionally done....
Bleed is the part of the image that will be cropped off when trimmed, Usually around 3mm. Its because printers don't print to the edge of the paper, cutting into the image prevents white borders around your pages. That make sense?
Also are you using a high resolution? Photoshop defaults to a horrrible 75ish, for print you need around 300+ DPI (Preferably 600) depending on what format printer it will be printed on....
There were a bunch more things I could have mentioned but I don't think anyone here cares about imposition and pantones and the like.....
I never got to do anything cool like this for school =( I had to wait until I got to work......