The only reason I want to know is to give myself the best chance of becoming lucid.
All the books I’ve read all say to look at your REM cycles to time your WBTB so it’s during REM and not deep sleep.
Seeing as my sleep cycles are pretty erratic (I don’t go to sleep the same time every night) I was hoping there was another way to tell if I’m close to REM.

I pretty much stick to DILD, as I’ve never managed to DEILD at all. I can’t just wake and go straight back to sleep (unless I’m in deep sleep early in the night, when I’m unlikely to LD). WILD doesn’t seem to work for me either... I have managed to get MILD to work once, and only once. So I just try and give myself the best chance to DILD (usually on a weekend when I can sleep in.)