If you prefer not to slip stitches at the edge for whatever reason, here is a nice trick: knit the first stitch regularly, but give an extra tug on the yarn when knitting the second stitch as follows:
First, a review.... To make a knit stitch, you 1)insert the right needle into the next stitch on the left needle; 2)yarn over on the right needle; and 3)pull the new stitch through. I know you know this, but bear with me.
Put your right needle into the second stitch as you normally would in step 1, but before you do the step 2 yarn over, give that yarn a little tug first. This tightens up the first stitch, which is the one that always looks raggedy. Finish working the second stitch as you normally would, meaning complete that yarn over, and proceed across the row. You will be surprised how neat your edges are if you remember to always tug and snug when working that second stitch.
The works very well for garter borders, which are common on scarves and shawls.
