How might one fall asleep instantly?

Instantly?: Not instant but good sleep hygiene will help. 1. Keep a regular bedtime & wakening time (to include weekends). Get up the same time each day, regardless of what time you fell asleep. 2. Make a regular, relaxing bedtime routine. Relaxing rituals prior to bedtime may include a warm bath or shower, aroma therapy, reading, or listening to gentle music. 3. Sleep in a dark, quiet, cool room on.

Instant sleep?: The only way to fall asleep relatively instantly is through IV medications like you receive in anesthesia. Even then there are a few seconds before you're asleep. Your sleep latency (time from full wakefulness to sleep) decreases with level of sleep deprivation. If you're very sleep deprived, you might fall asleep within 5 minutes. If well rested over time, needing 15-20 min is more normal.