In reply to Mattlloyd10:
I suffer from cold fingers worse than most people. Keeping them warm/functioning is a mini-science and is about a lot more than just the gloves you are wearing - in fact that isn't necessarily the most important thing.
1. Keep you hands warm and dry when not climbing.
On the walk in - mitts are great for that. I have a pair of BD ones with a separate inner compartment for the index finger, which makes belaying easier - they're about £100 but it's money well spent.
While gearing up - change into medium weight gloves which are dextrous enough to let you gear up (see 2 below re keeping these gloves warm).
On the belay - again, mitts are great but don't forget to periodically (this could mean every few minutes) move your arms to get the blood going - windmills, clenching and unclenching fingers and so on. After leading, your fingers should be warm but get those mitts on straight away anyway.
2. Keep you spare/belay gloves warm and dry.
Put your gloves in the pockets of your midlayer (I use a softshell underneath a hardshell, the softshell's pockets are ideal for this) or just put them next to your body inside your outer layer once your harness is on. Putting your spare gloves in the pockets of your outer layer isn't ideal as they will get cold. When climbing, you can similarly put your belay mitts inside your outer layer.
In the morning, fill a Nalgene type bottle with boiling water/squash etc, wrap a couple of pairs of gloves around the bottle and stick the whole lots in your sack, ideally against the back of the sack. When it comes to gearing you, your gloves should be warm and the water should still be warm as well - bonus!
3. Keep your core warm.
If your core is cold, the body will divert even more blood and energy to keep it warm, so your extremities will get even colder.
Invest in a good quality synthetic belay jacket with a hood which will easily go over your helmet and make sure you use it. Often when you've just walked in or led a pitch, you will feel pretty warm but it doesn't last long, so get that belay jacket on!
Keep hydrated and eat energy bars etc on a regular basis, even if you aren't hungry.
4. Keep your wrists warm.
Uncovered or partially covered wrists are a weak point because there are blood vessels close to the surface of the wrist, so you need to keep this area warm. Gloves with decent sized cuffs are preferable. You can also buy wrist warmers or make your own out of an old pair of walking or ski socks.
5. Keep the blood flowing through your fingers when climbing.
Warm the fingers up as much as you can before starting the pitch (again, windmills etc).
When climbing, relax your grip on the axes (this will make you less pumped as well) and take a hand off to shake out whenever you can (even if you aren't pumped, blood will flow a lot better if your hand is off the axe and handing free; I find that if I can stop and take a hand off for say 30 seconds, it will start warming up.
If there are any ledges, it's worth stopping for a few minutes and letting your fingers warm up. If they've got properly cold on the belay and the blood has drained out of them from some steep climbing off the belay, you'll probably get hotaches at this point. I have this concept of a hotaches ledge - a ledge a few metres off the belay and with some steep climbing to get to it.
Embrace the hotaches! If you get them, just stop and wait till they've passed, it will hurt but afterwards your fingers will be nice and warm.
Don't wear wrist leashes as they cut off circulation and make it harder to take your hands off the axes (hardly ever see anyone with wrist leashes these days but thought I'd include this).
6. Use thinner gloves for hard pitches.
This might sound counterintuitive but a thinner, more dextrous pair of gloves can work better on a hard pitch where you have to fiddle around with gear in pumpy positions. This is because you'll be able to get the gear in quicker, meaning less hanging around with one arm above your head. Doesn't really work when the weather is really bad but worth trying on a decent day.
Mountain Equipment Superalpine are my preferred gloves for harder pitches - dextrous, grippy, decent sized cuff and at £55 (or less with a BMC discount etc) not too expensive.
BD Punisher gloves are my preferred gloves for all other climbing.
I wouldn't waste money on cheap stuff. Better to save up and get something decent. Cold fingers are annoying at best and debilitating at worst...
I'm sure there will be more good tips out there.
Good luck!
Post edited at 01:25