The first thing you have to realize is that when you knit a stitch on the front, you're also creating a purl on the back. There is really only on stitch in knitting--it just depends on what side of it you're doing, if that makes sense.
If you knit every row, you're creating garter stitch, where you end up with alternate knit/purl rows showing on both sides. This will also happen if you purl every row.
In order to get stockinette stitch--where all the knit stitches are on one side and all the purl stitches are on the other side, you need to knit one row and purl one row.
"Trust the pattern!"
Time flies like an arrow, but fruit flies like a banana.
Hop aboard while we follow the cloud-covered van of knitting harmony, man!! Woooo!! --Hedgehog
IngridKH on Ravelry