Staying warm w/out wetsuit?

Hi - Short of it, I am allergic to neoprene and I am swimming in the Pacific Grove Tri this weekend (I practiced w/out wetsuit in the San Francisco Bay, it was cold, but I managed it…)… I would love any tips to stay warmer… I bought a long leg speedsuit to go over my short leg tri suit (both non-neoprene)… Any tricks of trade??? Vaseline type solution?
Thank you kindly, Sheen

Can you wear neoprene over the top of something? Frankly, I start to shiver after 20 minutes of swimming in our local pool anytime the water is below 75 degrees. I don’t even know if I could ride a bike after 30 minutes of Pacific Ocean swimming without a wetsuit. If it were me, I would be really creative about wearing a wetsuit over the top of something else. Otherwise, I would make sure I did a brisk warm-up beforehand and then I would trot around the beach before the stop to keep everything warm. It do that with a wetsuit and it keeps the initial shock of hitting the water to a minumum.
Chad