How do I warn Critiquers about the content of my story?
In step 3 of the story submission process is a text box where you can enter a "Content Advisory" warning. Here, you can enter the type of content you would like your readers to be forewarned about. If you have, mild language, adult situations, sexual innuendo, etc. here is the place to put that warning.
If you have strong or graphic sexual content (Not Pornography, which is not allowed at CC) or heavy swearing, you can also check the box in step 4 marked "The story contains language/material which might offend readers." This prevents underage member from reading this story. Keep in mind, however, that you cannot use this flag unless your story has explicit material. If the moderators determine that the flag was used simply to disallow crits from members under 18 year of age, the story may be removed.
If you have further questions, or you are in doubt as to whether you need either of these, you can always message the Moderators for a review.