I believe this one is the closest to screen accurate of all of the Amy Pond Scarf patterns on Ravelry.
I don’t think it’s very well written, though, so I’m re-doing it.

Also pairing this with a riff on Knucks.

…

Here’s my version of the pattern:

CO 24 stitches.
Row 1: Knit across.
Row 2 and every WS row: K3, P 18, K3.

For the scarf, work 3 border stitches in Garter, and center 18 stitches in Cable Pattern.

Cable Pattern:
Rows 1-6: work 3 border stitches in garter and center 18 stirches in stockinette.
Row 7: K6, C6B, C6F, K6.
Rows 8-14: work as for rows 1-6.
Row 15: K3, C6F, K6, C6B, K3.
Row 16: work as for rows 1-6.

Work until it’s as long as you want, ending with a Row 14.

add three 12” (total length of yarn) tassels on each end.