you can throw kit at some parts but understanding why you can get cold(er) can help a lot too especially areas where blood is near the surface of the skin e.g. wrists.
long socks help to keep your feet warmer and wrist warmers help to keep your hands warmer. i find these are worth an extra pair of socks/gloves.
more blood at the surface is your neck and my current favourite is an aviator silk scarf which i find more versatile about the neck/face than a buff. i have a hat so don't need a buff to use as one. a balaclava can be the best bet though. the scarf also bungs up the chimney gap at the top of your jacket.
depending upon the wind (so i carry a woolly hat too) i use a brimmed hat (tilley winter hat) which is great for keeping some of the wind off your face. the earflaps can be not warm enough but some earbags solve that problem. if you need extra warmth about the ears then earbags are the very thing.
as an aside the polyester wind proof fleece lined trews from uniqlo performed extremely well over the weekend and are my best bargain for a few years (£19 new and £13 in the sale).
http://www.earbags.com/
brilliant things
Edited: 08/02/2012 at 13:39