What is the trick to making ribbing look good?

I’m doing 2x2 ribbing and I can’t get it to look decent. When I go from k to p, the edge of the last knit stitch gets all loose-like and funky looking. What am I doing wrong, or what can I do?

People often have a problem with this. The only thing you can do is to make sure your needles are close together at that point and that the yarn is pulled snugly as you make the first stitch of the purl, enough to make the needles touch. Hold it firmly and you do the next stitch so it won’t loosten up too much.