Here's how to knit i-cord edges on your project while you are knitting. This is a great edge if you need a firmer edge like on a blanket or where you don't need much stretch, like a scarf. (Also known as Triple Selvedge.) Directions are also in video below.
+6 stitches RS (first 3 sts): sl1 wyib, sl1 wyif, K1 RS (last 3 sts): K1, sl1 wyif, P1 WS (first 3 sts): sl1 wyib, K1, sl1 wyif WS (last 3 sts): sl1 wyif, K1, P1 Repeat these two rows for the i cord edge. Happy Knitting.
