While reading an article from cracked.com, it explained a way to actually get your brain to hallucinate without having to ingest drugs, here are the steps:
You are going to need three things: a ping-pong ball, a radio with headphones and a red light.
Step 1: Turn the radio to a station with just white noise (static), and put on your headphones.
Step 2: Cut the ping-pong ball in half and tape each half over your eyes.
Step 3: Turn the red light so it's facing your eyes.
Step 4: Sit there for at least a half an hour.
This is called the Ganzfeld effect, what happens is that because your eyes are open, but seeing nothing but a complete field of redness, it will eventually turn off the visual signals to your brain. Then your brain will begin to start pumping out its own visuals. Same thing goes for sound. Good luck!
To read the full article, click me
To see an example, click here