I have a reason for using each of these techniques and directions for what I want to accomplish with each sock.
For the yellow sock (Georgian Bay Fibre Co. Bayfield Sock in McKellar Honey) I'm working on a new design, that I'm not certain of yet, so it may change considerably before the sock is done. For that I like designing cuff-down as it is an extremely popular direction for socks, so if I want it to be accessible to the greatest number of people, and I prefer decreases to increases, so this way I can reduce for the gusset and toe rather than working increases. So that makes cuff-down the right direction, and magic looping is my go-to default when knitting socks. I'm not doing this pair twinned, as I might do for a patterned sock like this because it is a design. My technique is to design the sock on paper, knit one sock keeping notes and tweaking the design as I go, then write out the pattern properly, and then try to knit the second sock working from the pattern so that I can check how the pattern is written. Then all the other stuff, tech editing, layout, review etc., but the two socks let me test my own pattern, because usually I've forgotten how exactly I knit the first one, so I use the pattern.
For the colorful socks (Spun Right Round Snappy Sock in Graffiti), I'm doing these as purse socks, and I like having my on-the-go socks on 9in circs because it means that I can work them and just drop them when I need to stop. No need to get to the next needle in magic loop, no worries about dropping a DPN. Also they are a published pattern, written cuff-down so I'm working that direction, However, I find with 9in circs I need to be doing only knits and purls (no cables, no lace) or my hands really hurt. So these Hermione's Everyday Socks are perfect for this sort of thing. However, I will be counting the purl bumps to make sure they are the same length!
Finally, the last pair of socks stripey (Turtlepurl Glitter & Stripes in Bah Humbug), I'm doing these toe-up because the person I'm making them for has small-ish calves so I can make the leg nice and long, and because Turtlepurl always come as two perfectly matched 50g skeins, the yarn is pre-divided so I can work them toe up and end when the yarn runs out (leaving enough to do the afterthought heels). Also, because they are self-striping and toe up, the afterthought heel is perfect, no gusset to be worked as increases and there will be no break in the stripes. Also, when working TAAT, the toe up method makes casting on super easy, using Judi's Magic Cast On, you can start them both at once on the same long circular needle, which means they will be exactly the same and done at the same time.
So I need to get back to my sock knitting, winter will be back before we know it and handknit socks are the best part of winter!
So how do you make your socks? Are you only cuff-down or toe-up? Do you only use one needle type or to you vary it by the project?