Swatching- how to measure?

I am making the Bernat free pattern- hooded baby jacket.

GAUGE: 22 sts and 30 rows = 4 ins
[10 cm] in stocking st. There is no st per inch recommendation.

So I stockinetted my little heart out (I didn’t cast off but left it OTN) and measured- I get 4" from top (not including needle) to bottom but only 3.5 in width (after uncurling the little devil and getting it flat.) Of course I can stretch it to 4"… The stitches looked nice & even, but when I knitted in pattern mine looked a little looser than the picture (OK! OK! I knitted the whole back piece already, but it isn’t my fault because I got my Harmony set Friday. I messed up on the pattern & will have to knit it over so I figured I would swatch better!)

Do I need to go up or down a needle or am I OK? Wasn’t this supposed to be square?

Here’s a great article on swatching. I often refer to it for reference.

If gauge is 22 inches I cast on 22 plus 8 more and knit 36 or so rows. It can be helpful to do seed stitch on the 4 outside stitches as they won’t curl. I then measure in several different places and measure only two inches and multiply by 2. I also bind off and throw it in water and dry and remeasure to see how much it stretches or shrinks. Only then will you really know … It would be hell to make a sweater thinking you had gauge only to have that sweater really end up being a huge swatch that didn’t work out.

Here are a few simple rules to calculate gauge: