When you get to the corner where the skip is done, you want to slide into it and then start spamming jump while still sliding. This will clip you through the wall and allow you to do the skip. The lower your framerate is, the easier it is to do, so I personally limit my framerate to 90. There is a large variation on the times you can get with this skip however, as even the world record for factory that uses the skip spends around a second tryin to get it.