Starting in a CST as a writer is the best way to get accustomed to it.
This can vary from story to story but essentially you either pick a character/make a character and in some cases a narrator (depending on the Creator's stipulations) and as soon as it is approved by the Creator as a viable character to the story: you can start writing! Once you start writing there are only a few guidelines to follow, to learn more about them read our community guidelines! Other than that, you have creative control over your character! Have fun with your character and collaborating with other writers and the creator!