Now that we've thoroughly covered foundation rows in crochet, it's the knitters' turn. Cast on edges usually do not pose problems in knitting. Usually, they are sufficiently loose or elastic for any project. What does pose problems, however, is binding off.
Binding off involves pulling the current stitch through the previous stitch, and doing that with every stitch across the row. With every stitch tangled with the ones next to it, rather than "borrowing" slack from each other, the bind off edge has very little elasticity. To get around that, one is always well served by trying to bind off loosely (NOT while angry). But sometimes, a little help can go a long way. This is especially true of cotton and other plant fibers, chenille, and some synthetic fibers.
Beyond that, your bind off row will be looser (and even) if you use a larger needle to bind off. I prefer to use a needle two sizes larger. With smaller gauges especially, you can also use two needles at once, although that can be awckward.
Another thing you can do, especially in larger projects, is increase in the bind off row. You can do this with whatever kind of increase you prefer. The idea is that before you pull the previous stitch over the current one, you increase in your current stitch. If you prefer the yarn over or make one increase, you increase, and then bind off the increase. It works best if you increase every few stitches (say, 6), but it can take a little trial and error to avoid increasing too much and making a ruffled edge.