Avoid consuming salt or anything that retains water like caffeine and Drink more water.
I suggest drinking plenty of water (like more than you think you need... more tha 2L)
Also you can buy socks/tights with slight compression for pregnancy... my friend used (FS4or8 socks cant remember the name but maybe google? I'd ask at the chemist first to be safe).
If you notice its excessive or moves to hands or face make sure to check BP with doctor xx