Avoid caffeine and nicotine.

Avoid drinking products with caffeine and avoid nicotine in cigarettes, vapes and gums. 

WHY IT HELPS:
Coffee, colas, certain teas, and chocolate contain the stimulant caffeine, and its effects can take as long as four-to-eight hours to wear off significantly. Therefore, a cup of coffee in the late afternoon can make it hard for you to fall asleep at night. Nicotine is also a stimulant, often causing smokers to sleep lightly. In addition, smokers often wake up early in the morning because of nicotine withdrawal.