Visualizing how a smoker works

The basic principle is quite simple. You need an air intake lower on your smoker to feed the fuel and some sort of wood to burn that creates smoke which swirls around the meat and exits through a vent higher up.

horizontal offset air flow smoker
Vertical Smoker Flow of Air and Smoke

Since heat rises, it creates a natural flow entering and exiting.

vertical air flow smoker
Offset Horizontal Smoker Flow of Air and Smoke

By opening the lower and upper vents, you allow more oxygen to flow through and this will increase heat and smoke.

What Do You Need for a Smoker?