I tend to have lucid black outs, where my vision will fade away, and if left that way for long I will wake up. I found a decent trick the other night.

Next time you lose your vision, pull down a set of "dream goggles!" Assume that you already had them on your head, and simply imagine pulling them down.

I tried this after my first successful WILD. Being determined to explore my first WILD, as I lost vision the thought sparked, and alas! I pulled down a set of goggles that were at my forehead, and vision returned, albeit a bit limited, but hey, it worked.

Hope this helps. =]