What does mean

I shuffled messages like cards, some to show and some to hide

As an AI language model, I don't have sufficient context to fully understand the intended meaning of this phrase. However, on a general level, it could mean that someone rearranged their messages like they were shuffling a deck of cards. Some messages were made visible, while others were kept hidden or concealed. It could imply that the person was trying to manipulate or control the flow of information.