For the bride and groom, much of their wedding day will be a blissful blur, with very few details sticking out enough to be remembered. As a guest, you have much more opportunity to notice and appreciate the little things. The wedding memory book, or guest book, gives you an opportunity to put some of those details down on paper for the happy couple so that they may enjoy reading about them later. The memories put down in that book will be cherished for a lifetime.
Think of a special sentiment or memory that brings the newlywed couple especially to mind. This may be a Biblical verse, a quote or even an anecdote about one or both of the betrothed.
Write out your sentiment or memory on a piece of scrap paper to make sure that you have all of the correct spellings, and that you are happy with the comment.
Use the pen that is provided to write your sentiment in the memory book. Writing in print rather than in cursive handwriting will make your comment much easier for the bride and groom to read. Also be advised that some couples use less traditional forms of guest books to record wedding memories, such as large photos of themselves with wide, plain mattes that are suitable for signing.
When writing comments in a wedding memory book, be yourself and use your own "voice" wherever possible.
If you choose to use an anecdote, be sure that it is something that is not embarrassing and that the bride and/or groom will not mind having shared.
If the couple is not especially religious, you may want to refrain from using a Biblical verse, as some people may be uncomfortable with having something religious in their memory book.