To do this, have a group of 2 people. One of them need a swap blaster and darkmoon tigers. It speeds up the method if both players have these since you can bypass the 3 minute cooldown on the darkmoon tiger. So what you need to do is go to a wall that you want to clip through, have the first player place down a tiger and the second player mount it. The first player then swap blasts them off the tiger. This will put you slightly infront of where the tiger was placed/ the other player was standing. Repeat this until you've clipped through the wall and then you can place down another tiger for the other person to jump through.
I found success trying this in everbloom where two invisible walls converge. After about 5 darkmoon tigers, my friend and I were able to roam around the instance.