What is the difference between a slip stitch and a single crochet?
A slip stitch is where you put your hook (with a stitch already on it) through the stitch, yarn over, pull through the stitch and the loop already on your hook. A single is where you put your (with a stitch already on it) through the stitch, yarn over, pull through the stitch, stop, yarn over, pull through both loops.
Why is my crochet blanket wavy?
Either it is too loose, so that whatever stitch you put into it pulls it out of shape, or it is too tight and pulls the other way. Or the chain itself can twist so you inadvertently put a curl into the project.
Does it matter which way you turn your work in crochet?
It may not seem like it matters, but turning in crochet ought to be done consistently each time. That is, you should be turning the same way every time you turn to the next side. The turn creates a neat edge, which is important if you are joining two pieces or seaming garments.