Avoid sitting for long periods of time such as on long plane rides or car rides.
If you need to sit for a long period of time, it is a good idea to flex your calf muscles by moving your foot up and down to increase blood flow back to your heart
from your legs. If you have been prescribed a "blood thinner" it is important to continue taking your medication as prescribed by your physician.
Answer assisted by Justin Fuehrer, Medical Student