Length of Floats
It’s no coincidence that most stranded-knitting patterns are comprised of small, tight graphic elements.
Technically, this serves to control the length of the floats. If the distance between colors in any particular row is extremely wide, a super long float will occur on the wrong side of the fabric.
This strand of yarn can easily catch on buttons or fingertips and also causes especially loose and sloppy stitches on each end of the float.
If the color work requires that you carry a yarn for a distance of 1"/[2.5cm] or more, you should catch, or twist, the unused strand with the working yarn.
There’s no hard-and fast rule about how far you can comfortably strand, but I’d recommend no more than 1"/[2.5cm] of width—that’s fewer stitches when working with a bulky yarn and more stitches for a fine one.
To catch a long float mid-carry while knitting:
Bring the floating yarn to the left and under the working yarn to catch it, then continue across the row, knitting with the working yarn only.
To catch a long float mid-carry while purling: Bring the floating yarn to the left and over the working yarn to catch it, then continue across the row, purling with the working yarn only.