If you are considering making big changes to your blog, particularly ones that require editing the WordPress source files, it's worth considering setting up a development environment on your local computer. This has a number of benefits. First, if you mess up and cause irreparable damage to the WordPress files, you haven't broken your live blog. Second, you don't have to take your blog offline while you're playing around under the hood. Third, you don't have to keep FTPing files to your remote server to view the changes.
Admittedly, most of the editing we'll be doing in the rest of this chapter could be done using the Theme Editor in the WordPress administration area. If you follow through the case study example at the end of this chapter, it will probably only take half an hour or so...