Hi, welcome to KH.
If you start both socks at about the same place in the two balls of yarn, at the same color, they should come out fairly close to the same. Doesn't always work but I kind of like socks that don't come out identical. Also, knitting 2 at a time would allow you to see how evenly the color changes are occurring.
This is the last time I'm frogging this project for the last time.