I have to agree with Goldenspark: if what you're doing now isn't working, then switch to something new. Most people here find it very beneficial to use the various methods to becoming lucid, and there's a reason for that. Pick out one and try it for a few weeks, and if that one doesn't work then pick out another. Everyone has at least one thing that really sets them off with lucid dreaming, and sometimes it's harder to find that.

(Also, have you tried napping? LDs are typically very easy to be had in naps, and it's personally my only sure-fire way of getting lucid.)