How do I choose what pages I wanna print??

Everytime i print out my book (when i bought it, i was aloud to print the book 1,5 times) but it prints out randomly - so now, after i've used 300 peaces of paper, I only got 75 out of the 300 pages the book is on. HOW do i choose what pages i wanna print? I've now printed the same 50 first pages like 4 times....