A diary is a great place to write about life, love, and all the secrets that no one else should ever find out about. Diaries and journals allow a writer to express her innermost thoughts and feelings without having to worry about anyone else reading them.
Make it inconspicuous. It will be easier to hide a diary (even in plain sight) and still avoid suspicion if it doesn't actually look like a diary. Avoid diaries with visible locks, elaborate designs and bright colors, and books that have the word "Diary" or "Journal" embossed on the cover or spine. Opt for a simple diary that looks like an ordinary book. If it looks like a regular book, there is a good chance it will be mistaken for one.
Hide it in another book. You can always hide your diary inside another book to keep it safe. Security stores sell hollow books that look like ordinary books on the outside but open to reveal a hollow space inside the cover that's perfect for hiding valuables, money or a treasured diary.
Skip the obvious hiding places that are always checked first, like under the mattress, in a desk or at the back of the underwear drawer. Get creative and hide your diary somewhere different, like in the freezer, the back of the silverware drawer or in the bottom of your tool box.
Make a decoy diary. Get a diary with an obvious lock and key, write some fake entries in it and leave it in a place where you know it will be found. Once someone has found the decoy diary, they'll assume that is the only one and your real diary will be safe.
Keep quiet about your diary. People will be less likely to look for a hidden diary if you don't tell anyone you actually have one. Don't mention places where you hide things or places that you think would make good hiding places.