This is my 150th free Ravelry design and it’s a perennial favorite! It’s in at least 4 different vintage publications! The earliest I’ve found was in The New Knitter or Lady’s Work Table Companion from 1848. My pattern revival is from Weldon’s Practical Needlework, vol. 1, p.6 from 1888. You could make a strip, a square or a one-piece afghan out of this pattern, all depending on how many repeats you wish to work. The top and bottom ribbed borders are also optional.
The Diagonal Design pattern has 10 rows and a multiple of 9 stitches + 3 more stitches for the design. I added 1 selvage stitch on each side. 5 of the 10 pattern rows are purl across. After working the 10-row pattern a few times, it’s highly likely you’ll be able to “read” your knitting and not need to reference the written instructions much after that.
The sample is 6 inches wide by 10 inches tall. It took me 20 minutes to work 3 inches of the swatch. (Bigger needles and bigger yarn work up so quickly!)

Skills needed: cast on, slip, knit, yarn over, k2tog, kf&b, purl, p2tog and bind off in k2, p2 rib stitch.

Gauge is not important in this pattern. Any block-able yarn/thread will work. Make a swatch to check gauge and appearance.

44 yards of Lion brand 24/7 Cotton will make 10 inches of a 34-stitch-wide strip in the stated gauge.