There really is no explaining this. Only experiencing it. Terence said it quite eloquently,
"You don't change. What happens is the world is completely... replaced! Instantly, 100% it's all gone. And what is put in its place, not one iota of what is put in its place was taken from this world. So, its a 100% reality channel switch. They dont even retain 3D space and linear time...reality is swapped out for something else, and you try to say what it is and you realize that language has evolved in this world and it can serve no other. So what you're looking at is literally the unspeakable, the indescribable."
Ive linked a few people particularly well written articles or even shown some The Spirit Molecule documentary, while its not a perfect, it really is a great introduction to the uninformed because of all of the accounts of people from all walks of life. It's all very captivating.
This is a great short too because the visuals are great and the background dialogue by Terence is very straight forward and easy for someone new to understand.
[YOUTUBE]
Even the How Stuff Works website has a channel on youtube and a series called "Stuff They Dont Want You to Know" and they featured DMT. IMO, it's the best and most focused introduction for someone on the topic because it is 4 minutes, right to the point, and puts out a lot of very intriguing unbiased information.
[YOUTUBE]