Let me start by saying that Vivian Clark does not have a said route you can take. If you refer to the "optimal route" document in the other guide you might notice that everything is segmented. This is because Vivian Clark involves a lot of RNG in what levels are best to do (primarily through the evaporation level and collectables RNG).

Protect this planet So far I have identified one thing that is worthy of always being done first. To get to the Make it to the end room, go down into the purple house and pop a bubble. Then as hamburger man go left into the angry yellow jumper. Make it to the end > find a way to evaporate (if you die just use bonfire) > protect this planet. "Protect this planet" is a difficult level to access so getting to that level first is key. The most reliable (almost 80%) way I found is to position yourself in such a way that you are in front of the heart shaped cloud(later I will make a youtube vid for this). Once the top half becomes darker and you still don't see the sprite dash to the left to try and catch one that might spawn further left.

Elephant book Elephant book route is also best done early as the fastest way of doing that sequence is to do "Cut the string" right before you deliver the book and then jump backwards blindly. This strat is not too easy.

Kill demon This one is very easy to choke on so do it early on so you don't have to choke on it 20 times in a row!

Save the Muffin! Same deal as Kill Demon. Choking Hazard is real so just do it at the start so you can reset on death (or 2 deaths if your PB is like +1:43).

The whole rest of the game The rest of the game doesn't have any specific routing yet. In general you should try to use the optimal routes that are described in the google document as much as possible but the order of the segments is mostly up to the run itself.