Talk with your commercial printer about your choices for page size, resolution needed for photos and graphics, page counts and files accepted for print. Each printing operation and its press may have different requirements which a printer will share, often in a prepared checklist, before you begin your design.
Create paragraph styles for your body type, chapter headings, page numbers and any other text elements you may use in the book, such as footnotes, an index or sidebars. Setting styles for each element ensures consistency and allows you to later adjust a style automatically across the book.
Use fonts that work with InDesign and with your commercial printer. Adobe recommends sticking with Microsoft OpenType, Type 1, PostScript, or TrueType fonts. While other styles are readily available on the Internet, they can create unexpected results if they don't match the recommended type.
Design master pages for each type of page you have, including the first page of a chapter, chapter body and pages for front matter (dedication, contents and forward) and back matter (index, endnotes). This ensures consistency throughout the book. Design the cover in a separate document; it will have different dimensions from interior pages because of the book's spine.
Transform any graphics or photos you use, such as resizing or skewing, in the original files before placing them in the InDesign file. All color and photos must by in CMYK mode.
Verify all fonts and graphics you use by running File > Preflight and fix any problems such as missing fonts or photos that need to be updated or relinked.
Package your book if the printer wants your InDesign file and linked files by choosing File > Package. Select Copy Fonts, Copy Linked Graphics and Update Graphic Links in Package. Copy the package folder to a CD or travel drive and take to the printer.
Export the InDesign file as a PDF if the printer prefers that format, which is increasingly common. After you name the export file, a dialog box appears, and a drop down menu asks which PDF preset to use, such as PDF/X-1a:2001, an ISO standard for graphic content exchange. Your printer will tell you which preset he will need.