Take these platforms up to the top of the level and walk to the right untill you come across the pipe labeled '5' leading to world 5. In order to get to this hidden warp zone, head to the end of the level until you see the last set of platforms moving in the up direction.

In World 4-2 there is a hidden warp zone that takes you to world 5. Repeat this till your character glitches through the wall and you can walk to the warp zone secret area. Next, you have to duck, and while ducking, you're going to work to jump backwards toward the pipe without breaking the block farthest to the right.

To perform the glitch, break the second to last block above you, then sand with one foot hanging off the pipe. This is the same area that takes you to the warp zone of worlds 2, 3, and 4 but using the glitch will make these pipes take you somewhere else. At the end of the level in 1-2 you will come to a pipe that leads you to the end-of-the level flagpole, instead of going through the pipe you can glitch through the top of it. In World 1-2 there is a glitch that will take you either to World -1 or you can use it to get to World 5-1. Each one will take you to the world of the corresponding number, the options will be world 2, 3, or 4. Ride a platform all the way up till you can jump onto the blocks at the top of the level and walk right till you approach three pipes. These particular platforms will be moving in the up direction instead of moving downwards like the previous one. While you're in World 1 - 2, head toward the end of the level where you will see the second set of moving platforms. This allows you to skip to world 2, 3, or 4. If done correctly, you will be rewarded with continuous 1-ups if you're able to keep going. The timing here must be perfect or you will end up sending the turtle flying.

Hit the second turtle to make him stop coming down the stairs and keep jumping so your character doesn't hit the ground. At the end of the level, you will see two turtles coming down the stairs that lead to the flagpole. To get unlimited 1-ups, go to world 3-1 and head towards the end of the level.

Super mario bros nes world 1-3