Video Tutorial

Cast on 80 stitches
Rows 1-10: Work garter stitch
Rows 11-70: 5 garter stitch edge, work stockinette stitch in the middle, 5 garter stitch edge
Rows 71-80: Work garter stitch
Bind off

NOTES

Garter stitch: Work all rows with knit stitch
Stockinette stitch: Work 1 row with knit stitch, 1 row with purl stitch