To keep stripes from jogging slip the last knit stitch of the new color. It helps make it look even. Does that make sense?
For example, imagine this is my knitting....w is for white and b is for blue...x represents the slipped stitch.
My rounds are in white. Then in the center round, the yarn changes to blue. I continue around and when I get back to that point of my knitting where I am knitting blue yarn into the last white stitch on the needle, I slip the next blue stitch instead of knitting it. That makes it appear not to jog.
does that make sense or did I totally confuse you?
AND having said all that... I did NOT use that technique on these socks. My gauge was so tight it wasn't readily apparent unless you looked super close so I let it go.