The best join is a join that is as invisible as possible. The best way to accomplish a nearly invisible join varies with the yarn’s fiber content, thickness, the type of project and other factors. If you're knitting something that will be sewn together later, it's best to join a new yarn at the edge so that the yarn ends can be hidden in the seam. Just finish the row, attach the new yarn with a loose knot and start the next row with the new skein of yarn.

But what if you run out of yarn unexpectedly in the middle of a lace shawl with 300 stitches on the needle? Are you going to “tink” back to the edge? I think not. And so many of those things knitters love to knit - socks, hats, mittens, raglan sweaters - are knit in the round and seamless... where to hide the join then?

The spit splice

The animal fibers that stick together well - think fibers that shrink and stick together when subjected to moisture, heat and friction, like in your washing machine on the hot cycle - are the easiest to join invisibly.

The oh-so-attractively-named "spit splice" is simply applying heat, friction and moisture to felt the two ends of yarn together.

First open up the fibers on each yarn end for about an inch or two...

then overlap the ends. If the yarn is thick you can remove about half of the fibers from each end to make the join less bulky.

Now apply moisture by sticking the overlapping area in your mouth. (You could also dip the overlapped area in a little warm water. You never know where that sheep has been.) 

Then rub the overlapping area between your palm and a surface. Your own leg in a pair of jeans is perfect.

Then hold the yarn on either side of the new join and introduce some twist in the same direction as the twist in the yarn...

and...voila!

I use the spit splice join whenever I can. It doesn't require any extra tools and makes a join without any pesky yarn ends that might pop out. Perfect!

An overlapping join

The join I tend to use most for yarns that don't felt easily is incredibly simple to work. It's basically joining the new yarn and weaving in ends as you go! 

(In the following pictures, I'm using two different colors of yarn just so you can see the process more easily.)

First loop the two ends together so that the strands of the old yarn are next to each other and the strands of the new yarn are next to each other. Make sure you have enough yarn between the join and the work in progress to knit about 3-4 stitches.

Now knit those next 3-4 stitches with the two strands of the old yarn ...

then 3-4 stitches with the two strands of the new yarn. Be sure to treat each of these stitches that are made of two strands of yarn as ONE stitch on the following row or you’ll wind up increasing by accident.

I honestly think this join is pretty darn fantastic. It adds a little bit of bulk BUT you're weaving in the ends as you go. And as we all know, weaving in ends after you're finished knitting is pretty darn boring. If possible try to position the join in a spot that won't be so obvious. For example, if you're knitting a sleeve, place the join at the underarm rather than at the center. 

The Russian join

If you're working with a yarn that doesn't felt and a project where it would be best to avoid yarn ends completely, the Russian join may be just what you're looking for. Lace is often knit loosely and with slippery yarns making it easy for any ends that are woven in to work their way back out. We definitely don’t want that.

Loop the two yarn ends together. Then thread one end onto a thin yarn needle and insert the needle back into the yarn - weaving it in and out as close to the core of the strand as possible. 

And pull through.

Repeat with the other end…

and trim off the stray ends. 

This join adds a bit of bulk and is easiest to work in a plied yarn. But with patience and practice and a small enough yarn needle, it should be possible to get good results with most any yarn. It’s also quite secure. In fact I couldn’t actually remove the join after taking these pictures and had to cut these two yarns apart!