Concentrate less on body, more on thought. I hate WILD thread that bombard the reader with "DON'T MOVE" messages. For many, this completely throws off the groove. They start focusing on the body, which is wrong.

Here's my suggestion: focus on thought. I don't mean "count to 100, check to see if you feel vibrations," I mean "count to 100, visualize your dream, count down to 0, visualize yourself becoming lucid, repeat." You shouldn't notice yourself relaxing at all. When I succeed at WILD, I notice SP as a sudden transition, not a gradual occurence. When I fail WILDs, I could go on talking forever about the 'deepening stages of sleep paralysis.' When I succeed, I can only remember a quick burst of SP.