I'm kinda confused on how to do the updoor clip. I lose a lot of time because I have to do the full level. Does anyone know how to do it consistently?

yup its pretty easy,

First I would recommend killing the two strays in the hall to get them out of the way but its not entirely necessary

Second go over to the far door and get close enough to open it. This deloads the previous room which is necessary for opening the hole to get oob.

lastly get on top of the previous door without opening it. The best way of doing this is to, from the far door, slide back towards the previous room and launch a core eject at your feet. Then continue to hold slide until you hit the far wall above the door where it should automatically force you to stand and you can jump oob from there. Alternatively you can move beside the first door and do a dive (Press jump and slide on the same frame) to get onto the door.

Just make sure that you dont open the first door after you open the second otherwise you need to go back to the second to unload the first area again.

If you have any other more specific issues with the skip feel free to reach out again or join the discord and ask in there and I or anyone else would be happy to help you.

thanks dude