When I visualize for WILD I never try to make it real, instead I think of a song or passively visualize myself walking in my house, and when the experience starts to feel more real well then I know that I can "transition" (I am actually already transitioned). I usually visualize Muse songs that I am used to hear but in my own voice but when I suddenly hear Mats voice (the singer in Muse) and hear "WHEN DARKNESS FALL AND SURROOOOOOOUNDS YOU. WHEN YOU FALL DOWN WHEN YOU'RE SCARED AND YOU'RE LOST. BE BRAAAAAAAAAAAAAAAAAAVE" haha well then I know that I am in state and I can either continue to visualize or just get up because I am then in dreaming state and my sesnations and awareness is in a dreambed.

So in other words I use the realness of the visualization as a reality check.

It's not that strange really, you can visualize an alien and well if you see it, it's obvious that you are dreaming.
I hope this shed some light on how I feel and perform the transition of WILDing.