Floats get especially long if your pattern has too many stitches between one color change and the next. You can carry yarn for stretches longer than 5 or 7 stitches, but pushing the traditional limits requires that you catch the float. If you’re knitting with one rather than two hands, you secure the float in the nonworking yarn (assume that it’s the MC) to the wrong side of the fabric:
Work a few stitches with the contrasting color (abbreviated CC).
Then drop the CC.
Bring the float color (MC) to the left over the CC and hold it loosely in your left hand.
You hold it so that it doesn’t fall.
Pick up the CC again and knit a few more stitches.
The MC (main color) will be caught against the fabric by the working strand of the CC.
Repeat these steps, if necessary, every 5 stitches or so until you begin working with the MC again.
Be sure that the nonworking strand remains relaxed across the back of the fabric and doesn’t pull up.