To make quite clear the Flagpole Glitch on PAL is quite simple requiring you to land on the right spot and timing the inputs correctly.

Note: For this Guide i will use 1-1 as an example however the information can be applied for every level in the game (That has a Flagpole)

To start play level 1-1 as you normally would, Clearing the underground section in the proses. After leaving the pipe run and jump over the two goombas and land on the pipe in front of the stairs (or bricks if you will)

Next run and jump from the pipe to the Fifth step, upon landing on the fifth step do a full jump to land in front of the flagpole block (No Subpixel Precision Needed on PAL)

If done correctly you should have landed in-between the two blocks in front of the flagpole base (The mountain in the background is a good visual que making sure Mario's back foot is touching the edge of the mountain) Note: Upon landing No inputs should be pressed!

At this point Mario should start walking towards the flagpole base top right (R) After two Frames and Hold it for another 3 to 4

After the forth frame Simply Do a small jump and Mario should Clip into the Flagpole Block (Executing the Flagpole Glitch in the Proses)

Note: These inputs don't have to be exact and can vary depending on your timing, This is just what I am used to

If you followed my inputs exactly it should look like this.

Land ----, R---,R---,R---,R---,--A-,--A- That's all feel free to message me if you have any questions...