Hi there -
I assume that you are asking about Wake To Sleep? This technique is used to break habitual wakings, but the name is sort of misleading. You don't actually wake the LO, but just get them to stir and therefore switch sleep cycles. Stroke their cheek, tug the blanket, whatever to make them stir. Not WAKE, but stir. To be effective, this should be done 30 - 60 minutes before the wake time.