help, what to do about swelling

almost 36 weeks.

for 3 days now I've had swelling on my legs and ankles! I am choosing to work until I go into labor...and I walk around all day long! I can take as many sit breaks as I need to. and I carry around a bottle of water all day, to make sure I'm drinking enough.

what can I do to keep the swelling at bay so that I can work an 8 hour shift on my feet??

**I had to leave work early yesterday because the swelling was getting too bad, and it hurt to stay on my feet. I really need to get through my shift today without leaving early.