If you just want to get general improvement from the dictionaries and factbooks. Just photoread them nightly for a couple of weeks and see what comes up. As in a sort of direct learning experience don't worry about activating them.
However if you have a specific goal and want to demonstrate you general knowledge then you would apply what ever memory techniqes you can get working for you on them. When learning a new language just PR the dictionaries of the chosen language regularly for a while... no activation required. It comes with the regular lessons or use.
Alex
