Well I believe the theory is that if you recall and have a dream journal it may induce more lucid dreams while you are sleeping as well as making them more vivid.

Like Gremlin said you may want to master the WILD technique which can be a little hard for begginners but once you master it like he said you will have LD's at will.

There are also many other techniques in the Tutorial section of the site that you may want to check out and find one you think to be best for you and get going with that.