Please give us a pattern name and/or a link to the pattern. If it's in a book you can type out the lines of the pattern that are confusing you. Don't post the entire pattern.
ETA: Wow...unless you edited the post I must have been asleep when I posted because I see you gave the pattern name.
It does still help to type out a few lines of the confusing part though.
Generally though mattress stitch is used to seam the most parts. 3 needle bind off on shoulders. Video instructions are in the video section under Tips and finishing techniques.