If anyone wants to do a Sublevel 35 speedrun, here is a cool skip:

1. enter the flip side.

2. go above where button 4 would be on the normal side.

3. lure the mirror smiler to you.

4. stand above the 4th button.

5. get hit by the smiler, getting sent back to the normal side.

6. hit the button and use the tp to go to spawn.

You can see a clip of it here: Sublevel 35 (youtube.com)

Goodluck and happy running!