A lot of good idea's in the posts
My first would be setting my umbrella so I am well protected from the wind
As many layers of clothes that I can get on and still move.
Bought a pair of socks for £39-99 ( seal skins ) water proof and thermal.
Seeing I did not go in the water and my feet where still cold they where a waste of money
For keeping my hands warm I swear by "Hotties", a little pack of chemicals that you shake, there on e-bay
stay hot for a long time, one in each pocket or if wearing gloves slide them onto the back of your hand
Steve