I use the bulky gloves that Omnipole supply, if you are WFP they are first rate, fur lined and water proof, and they do a top class job of keeping your hands warm and dry, and are very hard wearing.
If your hands have got cold, even in gloves they will tend to stay cold, you need to increase the blood supply to them.
you might feel a berk, but hold your arms loose, particularly the hands and fingers and then throw your arms around your body hard.
Keep your hands loose, throw your arms from the shoulders only and let your fingers slap against the back of your shoulder blades.
Providing you keep your hands and arms free and loose then you'll force the blood back into your fingertips and your fingers will glow!
To some of you that may sound like teaching granny to suck eggs, but some people can't do that for love nor money.
but if you can do it then it makes a hell of a difference.
Your fingers will stay warmer for longer in your gloves this way too.
Ian