I wrote the pattern for a one-skein scarf but I actually used a small amount from a second skein to make it longer. It ended up being just over 70” long. (Pattern scarf will be 48”.)

I slightly altered a version of a reversible cable scarf pattern that coriknits came up with (here).

Using one skein of Malabrigo Rasta on US 11 (8mm) needles, the pattern yields a 3 inch wide scarf with a length of 48 inches.

My version:
Note: Slip purlwise the first stitch of every row.

CO 12 sts.
Rows 1-7: Sl 1, k1, (p1, k1) 5 times.
Row 8: Sl1, k1, C8F*, p1, k1.

Rep rows 1-8 for a consistently placed reversible cable.

At the point where you want to finish the scarf (running out of yarn or you’ve reached your desired length) and you’ve knit the last row of your final 30-row section, cable again as above, work 8 rows more in the (k1, p1) rib, cable once more, work another 8 rows, and bind off.

*C8F = Slip the next four sts to a cable needle and hold to the front. Knit the next four sts in the (p1, k1) rib. Now work the four sts from the cable needle in the (p1, k1) rib.

For mine, I alternated between two cables (8 rows apart) and a single cable. I left 30 rows between each cable and the next set of cables.

/
X (cable)
X
/
/
/
/
X
/
/
/
/
X
X
/
/
/
/
X
/
/
/
/
X
X
and so forth…