First, choose a theme for your book... whether it's your family, your kid(s), a wedding, vacations... avoid mixing themes within one book.  Mixing themes causes the book to not flow as smooth as it could be.  Go through your book and designate a particular topic, type of layout, timeline of events, and or specific pictures you want to use for each page prior to actually starting any pages specifically - mark ideas, etc on a post-it note to label each page so you don't lose your ideas.  By doing all of this will also help your book to flow more smoothly and will be more appealing to the viewer.  When choosing papers and accessories try to coordinate them with the colors or with items found within the pictures you are using for that particular page. Also, another good idea is to use similar pages on say, pages 2 and 3, because those two pages when laid open will appear at the same time.  Doing something that does not coordinate with one another can be distracting to the viewer.  Also, if you find a particular layout that works for you, don't be afraid to use it over and over again... just be sure to swith up the colors, frames, accessories, or perhaps do a mirrored verion of the same layout to promote diversity.  And remember - it's your book!  You can design it anyway you like, but applying these simple tips, will be extremely time saving and will give your book the feel as if you were reliving your memories all over again --- Happy Scrapbooking!