Schlage's website provides the official Schlage rekeying manuals, as of 2015. The manuals have instructions on how to rekey different kinds of locks including deadbolts, levers, knobs, and keypads.
Navigate to Schlage.com. Click on Support, then click on How-To Center. Click on Manuals & Templates, then select the Rekeying Manuals category. Click on the link for the appropriate rekeying manual. The manual either appears in your browser window or loads as a PDF file on your computer.
If the manual doesn't provide enough information, call Schlage at 888-805-9837. Alternatively, you can ask them a question by clicking on Contact in the footer then entering your message in the text field.