Before we move on to how to make endings, I want to show you how to skip dialogues even faster

to skip dialogues faster, hold down the X and mash the dialogue buttons to enable automatic dialogue skipping, in the Main Menu of the game go to Settings -> Game Settings and set Skip Dialogue to Yes, here are the videos that show you the difference between skipping dialogues

No mash:

With mash:

it is recommended to use the keyboard because you can hold down the X to automatically skip dialogues and at the same time mash with 2 keys at once to skip dialogues faster, on the controller this is not possible because you can only spam with one key to skip dialogues and it is not convenient to mash

How to get all known Endings: (author by @DarkHeart ) True End K1 - Curiosity Killed the Kat: Complete the ritual and open the door at the end of the long staircase. You can use either the key or you can pick it. The 2nd option is more viable in speedruns. You can ignore the "Let me show you something" room. Dead End K2 - Cold Kat Feet: Going out of the occult club room go to the left and try to go downstairs. Examine the stairs again and select "Yes, this is scary" Dead End K3 - Academic Spiral: Setup the ritual, when the "Point of No Return" triggers(read below) go to the left door (the same one from K2) and select to go downstairs. Keep doing down until the chalk experiment. Go down the stairs once again. Dead End K4 - Nevermind Forever: Befriend the girls(check below if you don't know how to do it) but do not cross the "Point of No return"(check down below). Try to leave the school via any of the two exits on the bottom of the main hallway (respond affirmatively when prompted). Dead End K5: - Party Wipe: Befriend the girls. Ignore the Storage Room (alternatively you can examine the door, examine the room itself prior to the "Point of No Return", or even after the Point, but make sure to leave the room before reaching the end; but all of this just extends the game) and continue the Ritual as usual by drawing the lines and placing the candles. The K5 ending will trigger after the candle part. Dead End K6 - Snip snip: Befriend the girls. Do not cross the "Point of No Return". Get the scissors (if you don't have them already) and cut a "happy plant" with the girls in tow. They will comment on Kat's plant-genocidal tendencies and leave, leading to this ending. Dead End K7 - Girls' Night Out: Befriend the girls and add them to your team. Gather all the ingredients (but do not bother with chalk lines or candles) and only then examine the storage room door in order to be given a task to enter the room. Get the hairpin from Kat's desk (if you do not already have it). Make sure you passed the "Point of No Return" by entering one of the classrooms (music in the hallway must be absent); pick the lock. You have only one attempt. Do not leave the storage room, ever. Proceed further until the end. Dead End K8 - My Way: Do the ritual alone, run through the study (where little Kat and a man in the chair are) without exploring, and choose "Be strong" in the small room. Then the voice go silent and Kat stay there forever. If you do explore the study, the option will not appear. Some clarifications:

1. Befriending the girls: Do not upset them in any way: do not cut their hair, do not try to mess with the bag. The fastest ways to do it are as follows: If you're doing K4 do this: Ignore class 3-A but deal with classes 3-B and 3-C, interact with the window without curtains, get Ponytail Girl's notebook, interact with the door of the theatre club, after talking to Ponytail Girl she will give you the key, then enter the theatre club, give back the key, turn on the radio then talk to Juli until you finish the dialogues and sit down and then leave the school. If you're doing K6 do the same thing as in K4 but: 1) don't ignore class 3-A 2) get the scissors If you're doing K5 or K7 do this:
2. Solve class 3-A (get the hairpin if you're doing K7)
3. Solve class 3-B
4. Examine the window with the missing curtains
5. Solve class 3-C
6. Examine the Theatre Club room
7. Get Ponytail Girl's notebook. It is located in 3-C, under the third upper desk when counting from the right side.
8. Go to the Occult Club room with the notebook.
9. Open the Theatre Club room.
10. Get the curtains.
11. Go back to the Occult Club room and give back the key to Ponytail Girl.
12. Do the rest as in K4.
13. "Point of No Return": The "Point of No Return" triggers when:
14. Kat has a rune, candles (these are available from the start), chalk and hair in the inventory;
15. All classroom windows are closed with curtains;
16. Kat is in a classroom. Thus, it can trigger in two ways: Either Kat can collect the materials first and only then enter a classroom and close the last window. This way the point will be crossed upon the window closing. Or, Kat can close the windows first and only then collect the last ingredient (like, by cutting a girl's or own hair) in any other room (or a hallway). This way the Point of No Return will trigger the instant Kat enters a classroom (any of the three shall do). Sudden music fade-out is a telltale.