General etiquette is that if you're posting something that might reveal major plot points or anything someone might wish to find out for themselves (e.g., why does Skylar's mother dislike the MC,) put it in a spoiler.
You can do this two ways: ispoiler (in []) will give you the smudged text. I use this frequently when I want to obscure only part of what I am writing and give a hint to readers whether they might already know what's smudged out. Or spoiler (again in []) if you have a coherent block of text you want hidden. spoiler is also good when posting large images, and Ren'Py error logs because it collapses into a button that says "Spoiler." Close either of them with the same text in [] except a "/" in front of the word.
You may slip up (I'm sure I have) and accidentally reveal something you didn't intend. Unless it's a super major plot point (e.g., the highly unlikely speculation that the MC is his own father and that of all the girls) I wouldn't worry about it.
