Try soaking feet in a tub filled with warm water with sea salt.Don't sit or stand for a long time.

Fluid retention which could be caused by : 
1. Elevated blood pressure which should be checked by the doctor. 
2. Being in one position for a long time which means that you should take frequent breaks and move around. 
3. Excessive salt intake which can come from packaged foods so take care of the same. 
4. Increased intake of foods high in saturated fats like ghee butter etc. Reduce intake of saturated fats in your daily diet.

swelling on hands and feet in 9month..whts the reason and remedy