I've worn waders for a number of years now, but have never wanted to fork out big dollars. So I have only use the PVC type.
If you have purchased the size above your normal foot size (hope so), then 2 pair of socks is best - as with 1 pair you'll find your feet are not 'snug' fitting, like wearing untied shoes.
I wear track pants and always tuck the legs into the socks - this stops the tracky legs riding up your leg when putting waders on. On very cold days I will have some bottom thermals as well.
Then I wear an old long sleeved cotton shirt (warmer one on colder days), but i