OK, I'll chime in here too ...
I use a hemmed top on mitten cuffs, and put elastic inside (attach a safety pin to the elastic, shove it inside the hem-cuff, and work it around, then work it back out the going-in spot, sew the elastic's two ends together and let it "disappear" into the hem.
(PS I also used it on the "evening bag" for DD -- with an extra row of eyelets below the hem, to pull the cord through.)
Gotta keep those little ones' hands warm!
I usually use about 10-15 rows 1/1 ribbing at the top of socks, then 3/1 down the leg. On a 54/36 arrangement, I'll use a 2/1 ribbing all the way down the leg.
As long as I knit them tight enough, they stay up fine. If they are loose going on, I knit them too loose, and I know they'll sag -- or come off with my shoe. So I tink those with a ball-winder and reknit them.
(posted by me this day on sockknittingmachinefriends)