This isn't a pattern I would ever recommend to a beginner. You may want to set it aside to finish after you have more experience.
I think the easiest way to piece a Carpenter's Wheel accurately is to draw it on freezer paper first with a permanent Sharpie. Cut out along the lines, then iron the freezer paper pieces to the right side of fabric. Cut the fabric, leaving 1/4-inch seam allowance. Leave the paper on as you piece. The edges help you line up the seams accurately, and the freezer paper keeps bias edges from stretching.
Oops! Sorry, I think I have confused this with a different quilt pattern -- can't remember the name right now. Not sure this method is best for your needs.