Try doing a search on this topic on clubsnap, u can find tons of them. Like what Mr Artosoft always tell ppl, the blue beads are not good for health. I believe the ultimate solution will be getting a dry cabinet. I also believe that u asked this question because u don intend to get one (at the moment).
An alternative to using the blue beads directly will be as follows:
Read the stuff, it is quite self explanatory. U can get them at home-fix for about $20.
I am a happy user of thirsty hippo. U can try to use those sachet type (so u will have no leakage problem). I get the original thirsty hippo, break it open to get the white white thirsty thing inside (dunno what u call it, i just know it absorbs moisture), get a small container poke some holes and lay some toilet paper inside, and put a bit of the thirsty thing on top of it. After a while, u will get used to it, and u'll know how much is needed to attain a RH of 40-50%. I use this method as it is more economical and easier to control RH than using the sachet.
Hope this helps.