does cast on count for one row, or does the next row ie, knit or purl count as row one>?
When making swatches to check for gauge
When knitting a gauge swatch, I usually make it 50% bigger so that I can measure stitches “in the middle” and get the most accurate measurement. For example, if your gauge says “16 sts and 20 rows”, I would cast on at least 24 sts, and knit for at least 30 rows. Then I can measure a few stitches in from each edge. Your tension usually is quite different on the first/last stitches of a row, and your cast on/bind off will be different from your “regular” tension as well.
^^ awesome advice!!!