Hi. I'm assuming you all know how to visualise. I'm not going to teach you how to do it, instead I am just going to explain the basics of this particular method. I created this using my own ideas, along with an idea that I picked up on this forum (I can't remember who posted it) to use a staircase.

So, without further ado, let's start by explaining the basic idea of my visualisation.
It is set in a tall building, with 100 floors. It doesn't have to be 100, it can be any number you want. The basic idea is that you start at the top (or bottom, if that's what you prefer) and as you walk down/up the stairs, you can see the floor number on the wall. On each floor, there is a door. This door can lead absolutely anywhere. When you've finished there, you go down/up the stairs to the next floor. You see the next number on the wall. Next to the number is a door. You open the door. Where does it take you? This is the basic idea.

Now, I'm going to explain part of a vis. which I wen't through a couple days ago.

I started at the top floor. I was on a balcony, overlooking a city. I turned around, and saw a big, orange '100' on the wall. There was no door on the top floor. I started to walk down the stairs. I put my hand on the banister, and felt it's cold, rusty, metal texture. I counted the steps it took me to get down.

I saw the '99' on the wall, and next to it, a generic grey metal door. I walked towards the door. I touched the handle. It was cold. I opened the door, and entered into the middle of a bustling city. While taking in the sights and sounds of the scene, I hailed a yellow cab. I opened the car door and sat down in the back seat. Comfy.

The cab driver started a conversation with me. Asked me how I was doing, where I was going. The thing is, I actually didn't know where I was going, so I stayed silent. I made up all sorts of different sights and sounds, as I looked through the car window. I felt the motion of the car as we travelled through the city.

The cab driver pulled up in a generic looking street. It thanked him and said goodbye. I walked towards another door. I opened it and stepped through. I was back on floor 99.

Walking down the stairs again, I put my hand on the railings and tried to make it feel as real as possible. Halfway down the stairs, there was a lady sitting on the stairs. I asked her name, and she said it was Chloe. I asked her what she was doing. She said she was waiting for someone, but she wouldn't tell me who. I continued down the stairs, and arrived at floor 98. The walls were a light blue colour, and the 98 was green. The door was yellow. I put my hand on the door handle. It was warm. I opened the door, and stepped into a quiet beach scene. There were a few people chilling on the sand. The air was hot, and decided I should change my clothing to something a little more appropriate. I lay down on the beach, making small talk with the others. I could hear birds, and the waves of the sea, and I could feel the sand beneath me.

I could go on all day, but you should get the idea.

The rundown incorporates a repetitive aspect of walking down stairs and opening doors, but also leaves alot of room for your imagination to run wild behind each doorway. You could also change it up to suit your own preferences, for example you could use an elevator instead of stairs.

I hope this helps you all.

TL;DR: Walking down a stairway, each floor has a door. Create a different scenario behind each door.