One thing you will have to decide for yourself is if you want to passive-WILD or V-WILD. V-WILD entices visualising yourself into the dream where the passive WILD has you to watch HH/HI until you fall into the dream.
Remember, what WILD means is to transition from waking state right into a dream while maintaining awareness. If you choose to maintain a level of awareness instead of visualising and let sleep take you, depending on if you balanced that awareness correctly you may;
a) not be able to fall asleep (too much awareness)
b) fall asleep and get into a non-lucid dream (not enough awareness)
c) fall asleep and into the dream (the right amount)

Don't stress out, WILD can take a while to perfect and is usually deemed one of the hardest techniques as it requires so much dedication and practice.