Maintaining a low level of awareness as I fall asleep.. How is it accomplished?

I'm clueless when it comes to what I should be doing with my mind. So far, I think I'm fairly good at handling everything else. My eyes are relaxed and stationary after the first 10 minutes or so, I always do WBTB, I have no swallowing problem, I can keep my body relaxed and still for quiet a long time.

However, what do I do with my mind? People say "you should be falling asleep as if you're not attempting WILD" but when I do that, I let my mind wander freely and fall asleep. So somehow I have to keep my mind slightly awake with an anchor, but I'm not sure how to do that appropriately. My anchor is a combination of white noise(iPhone app, good stuff) + the third eye of chakra. Here are some of the questions I've had.

1) Should I have the anchor on the foreground and free thoughts on the background? Or is it the other way around? (I mean, spend 70% of the time concentrating on the anchor and 30% of the time having some free thoughts?)
2) As I'm concentrating on my anchor, there comes a moment where I find my mind wandering. Then should I just let it wander, or should I try to empty my mind and come back to concentrating on my anchor?
3) Should I be imagining something visually?

What almost worked for me last night was keeping my attention on my breathing, feeling my body relax further and get closer to sleep with each exhale, and waiting a second before inhaling. You have to do this without thinking about it too much, just calmly keep your awareness on it. Other times I've been successful by focusing on imagined movement as I let my body relax.

1) I'm not sure how to answer this one. Maybe someone else can answer it better. For me, I try to have as little free thoughts as possible, so my mind doesn't get distracted and just fall asleep.
2) I think your mind should always come back to your anchor eventually. That's what's keeping your mind awake and aware. If your mind wanders off too far, you might just fall asleep and start a non-lucid dream. That's been my experience, anyway.
3) This probably depends on the person. It is probably not necessary. But maybe you could try it a few times with visuals and and a few times without to see which works best for you.

Hope I was somewhat helpful. I'm still fairly new at this too.