@fightfascism The most important thing to remember when planning out a way to pass secret messages using steganography is: Be original!
If it's widely known that someone can hide a secret message in a particular way, say, in the lower-order bits of an image, then strangers already know to look in that place for messages -- strangers including the folks that you don't want to read your messages.
Be clever and subtle and original. Find a new way to hide the information that no one has ever used before. If no one has thought of it before, they aren't very likely to think of it now, either.