Dizzy/lightheaded what do you do?

I know with the increase in blood production and flow and baby taking lots of it and the body rerouting blood it's typical to get dizzy. I was wondering, because I've had it bad twice all day, what helps you? The hard part is my job requires standing/walking all day. I try to move slowly when standing up, eating every two hours and drinking a lot of water but none of that is helping. I'll ask my doc on Wednesday when I go in but until then....