Here are a couple of knitting tips on how to join yarn. The first concerns joining yarn when one skein runs out. To splice yarn when knitting or crocheting, first thread the end from the new skein into a tapestry needle. Insert the needle into about three inches of the skein end you have been using and draw the new end out for about four inches.
Take off the needle and carefully pull the extra length back so it just barely goes out of sight within the splicing area. By fingering the yarn at the two contact points, the splice will hardly be noticed and you will have no knots or loose ends in your knitting.
Then, when knitting a cardigan – or any garment where you should have two parts alike, such as fronts or sleeves – use separate skeins of yarn for each piece and work both pieces at the same time.
This will avoid confusion in counting decreases and increases. And, of course, each piece will match the other perfectly. Just be sure to use needles long enough to easily accommodate both pieces. Straight needles will usually need to be 14 inches or longer – or work back and forth on circular needles.