When you're first starting out, it's best not to focus on what you have to give up - your favorite foods, your TV time, etc. Instead, spend the first week or so adding things - more water, more sleep, more fruits & veggies. Then slowly start focusing on what you need to give up. By adding first, you won't feel as much like you're depriving yourself.
Pretty sure I got this from The Spark book, but I may have seen it somewhere else.