Basically a spit splice with the strand ends wrapped like a pinky promise, this is a strong and wonderful way to join colors at the fabric edge when working flat. It looks like the colors magically changed (amaze your family and friends!), and reduces any bulk from ends woven in.
It also works great for joining yarn strands of the same color invisibly - even in the center of the fabric.
To splice: For each strand, separate strand into 3 plies for a 3-ply yarn (or roughly equal portions for other yarns); break one ply off 3" from end, break a second ply off 1.5" from end; twist two short ends around each other; lay twisted strands as shown above flat in palm of hand, moisten and rub vigorously to felt together.
To position splice at end of row: Work to end, break yarn leaving a 1.5" tail, frog back 6-8 stitches, splice, work to end. Voila!
Tip 1: If you'll be doing quite a bit of splicing, measure the strand after frogging back and before splicing, so that this same length can be measured 6-8 stitches before every splice.
Tip 2: Use your hand as your ruler ... you don't need to know how many inches of yarn to measure, just how far it is down your palm from your fingertip.
Note: Russian splicing and spit splicing only work on woollen yarns.