Pressfield wants his reader to become familiar with where resistance begins. He makes a list of the usual places they start, such as with one starting an exercise program, or having to learn new skills. In short, he notes that resistance will initiate at the “act that rejects immediate gratification in favor of long-term growth, health or integrity.” He gives other good examples where resistance might show up such as with any addictive pattern of lifestyle - drugs, alcohol, shopping, work, sex, food, tv, etc. He suggests these are forms of distractions, and to not feed them.
I encourage you to buy a copy of The War of Art for a better understanding of your own creative process. Whether you're a master artist or beginning artist, this is an excellent book.