Varicose veins are attributed to valves in the legs not functioning properly. The valves are like the little levers on the arcade game. They are not working properly so the blood flows slightly back at the valves resulting in swelling at locations in the body. Heard of ulcers with the veins.
Some things to consider - avoid standing, if you can sit then do so, if you can put your feet up fine. Walking helps others said and finding a suitable job I recommend.
People say wearing medical stocking helps, I was told years ago the stockings help with the valves and back flowing, don't get much trouble with mine but agree hereditary, others can confirm?