Cold hands are something everyone has endured. (And if you have Raynoud’s syndrome, where the smaller arteries that supply blood to the skin constrict excessively in response to cold, this can be especially problematic.)
Here's a solution - “windmill” your arms. The centrifugal force from doing this moves blood into your fingers and hands.
(Conversely, a lot of people will blow into their gloves, thinking the warmth from their breath will help warm up their hands. It actually has the opposite effect, because the water vapor from your breath chills your hands even further.)
Check out the short video below from the excellent MedWild YouTube channel.