What kind of suit are you using?
Have a look in the elios web page (
http://www.eliossub.com/html/spot1.html ).. they have great info,.
Open cell suit means that the neoprene has been cut leaving the oppen bubbles of the neoprene on one of the sides of the material. He becomes really flexible, what enable to tailor a perfect fitting suit with no zips, and therefore get an warmer (less exchange of cold water) and more flexible suit. But they are more fragile and can be a pain to get on.
If I'm cold I swim hard and fell better. Thick gloves and booties and in the extreme a facial mask.
Is a tread somewhere about warm up suits (try the find function).
If nothing works get get a dry suit and plenty of fleece: Ok for snorkeling or diving, but forget about freediving!!!