Being a cold feet person myself I have two tips to offer. Firstly, do not go to bed with cold feet because they will take hours to warm up. Secondly, you are often better off adding more insulation to your core and head area than to your feet.
It took me a while to appreciate that I could make my feet warmer by adding insulation to my core/head rather than directly to my feet. It makes sense though, because insulation does not produce heat, it just helps keep in the heat that has already been produced. If you get extremely cold feet (like me) then your feet are probably not producing enough heat because there is not enough blood flowing around them. This happens when the body restricts blood flow to the extremeties in order to keep the core and head warm.
So... even if you feel your core/head is "warm enough", you should still add more insulation to this area in order to warm your feet up. You can try it at home and see how quickly the effect works. Once you add extra core insulation you get toasty warm and blood flows to your feet freely once more.... resulting in nice warm feet. I find that once my feet are warm in my sleeping bag I don't have much problem keeping them warm for the rest of the night.
If you want to achieve this effect without adding much weight, then extra head insulation is your best bet. If you have a down jacket with you then definitely wear it. The other alternative is to do some vigorous exercise immediately before you get into bed. Do it until you feel yourself getting hot under your clothes, and then hop into your sleeping bag.
Works for me, so try it if you haven't already. You can also wear a liner sock, followed by a plastic bag, followed by a thicker (loose fitting) sock. The plastic bag acts as a vapor barrier and will keep your feet warmer. The main thing is though, the heat has to be in your feet to begin with in order for the extra insulation to work... and heat only comes from blood flow (or a hot water bottle, which is another idea you make like to try).