Did you set up your image plane correctly?
THis is what I'd recommend..the best part about knowing you've learned something. If the technique in the book isn't working exactly, revert to using basic shapes to shape the sword. A cube or cylinder.
Adapt when you hit a roadblock, this is how you know you have learned techniques to accomplishing what you need done. And of course, never stop asking questions.
That's my recommendation
If the way in the book isn't working as you expected, do it another way just as long as you can get a similar or same result. Shaping the sword, you can also use a nurbs or polygon plane I gather.