Ever wondered how difficult it is to weave with yarn that has long sections of color? (like handspun or Noro) How do you manage to get the color sequence to match up when winding your shuttle? Actually it's not too difficult, it just takes a little extra planning unless you have a stack of extra stick shuttles or bobbins.
yarn, 2 bobbins or shuttles that are exactly the same, small postal scale, paper and pencil (or calculator)
Start with winding one bobbin until it is full, and cut the yarn from the main ball. Weigh both the full bobbin and the empty one and find the difference in their weights. (For example my full bobbin weighed .87 oz, and the empty one weighed .32 oz, .87 - .32 = .55, so there was approx .55 oz of yarn on the full bobbin.)
Next wind your skein of yarn into balls, weighing as you go to make sure none of them are heavier than your calculated weight. Note: Be sure to keep track of the order that you wound the balls.
Finally re-wind the first bobbin directly onto the empty one (notice how the yarn tail that was the first you pulled off your skein is now ready for you to weave first). You are now ready to begin weaving. When you are finished weaving with the first bobbin of yarn, then you can continue by winding the first (then second, third, etc) ball to your shuttle.