I measure the width of the top of the front of my foot. Then I figure out how many stitches to cast on using a provisional cast on method. I do a toe with wrap and turns, figuring out as I go how many I need. I try them on as I'm doing it (these ones were actually for a friend, so I found the measurements of her size feet online and just measured). I don't count rows or stitches. Then I just knit a tube until I need to turn the heel. I should be knitting these two at a time, then they would be the ultimate socks, but I haven't quite figured out how to do that yet... maybe next pair.
I like toe-up socks because I am lazy, I like to try things on as I go, and like to get all the important things done first (toe, heel) so I can just go go go and don't have to worry about running out of yarn.
My tip about yarn: if you're learning use BIG YARN. Worsted, or aran, or even chunky (like these ones). They make big socks, but they also won't take you absolutely forever (I knit one of these socks over a 24 hour period). Always have nylon included. These were a wool/acrylic/nylon blend that works great for beginner socks.
I learned how to knit socks from Very Pink on Youtube. Her tutorial on toe-up socks rocked mine right off!
