My personal habit is to knit socks toe-up. I wouldn't say it's a preference, because I really don't mind either direction, but the first socks I made were toe-up so that set the norm for me. Of my own designs, I currently have nine pairs of socks in my pattern portfolio, with two more in progress. Of the eleven in total, seven are toe-up and four top-down.
The photograph above left shows my No Flies On Us which are worked toe up, because of the stitch pattern. The way the flies are constructed means that if the socks were worked top-down, the flies would be upside down!
The photograph above right shows Wengwings, which are top-down socks. They could be worked in either direction, but I wanted to get to the colourwork (i.e. the fun bit!) straight away, even if it does mean knitting the penguins head first!
The main issue knitters seem to have with the direction of sock construction is the toe, closely followed by the heel.
Toe-up socks begin with a provisional cast-on, which can look scary until you get used to it. There are a number of different methods, of which I tend to use the figure-8 cast on most often as I can work it without having to check a reference to make sure I've got it right to start out.
Conversely, top-down socks, which end with the toe, need the toe closing up, commonly using Kitchener stitch. Again that's a bit of a Marmite issue with some knitters loving it and some hating it. Personally I love the magic of it every time.
The other sticking point is the heel. Top-down preferrers sometimes say they have difficulty knowing where to start the heel on a toe-up sock. Yes, I will admit the start of a heel on a top-down sock is easier, but like many things it comes with practice. From experience I know how much foot I need to work before I start my preferred heel. A bit of maths helps too. If you know your row gauge and how many rows the heel is worked over, you can work out how much of the foot the heel will use.
For me, the advantages and disadvantages of each are as follows:
Advantages: more practice so greater familiarity, the sock is worked the "right way" up, if I'm short on yarn a shorter leg is better than a short foot (!)
Disadvantages: it can be tricky to get the cast-off loose enough without being too loose, by the time I get to the leg I'm getting bored (I must admit to at least one pair of socks with legs that ought to be an inch longer really!)
Advantages: no fiddly cast-on, easier to work out heel placement
Disadvantages: grafting the toe, need to know you have sufficient yarn, personally I find it tricky to know exactly where to start the toe shaping
As an experiment I recently designed a pair of socks which I originally intended to work toe-up (yes, I'm a creature of habit, what of it?!). Having finished the first one, I decided to see if it was easy to reverse the pattern instructions and make the second sock top-down without it being obvious. The answer? Even I can't tell which sock I worked in which direction without looking very closely! I'll be writing up that pattern very soon!
How do you prefer to work your socks? Top down? Toe up? Or some other construction?