Brief Answer:
depends on the cause

Detailed Answer:
Hello,

getting rid of it depends on the cause. There are various causes...
- heart failure: causes shortness of breath and swollen legs. Getting the legs higher than your body helps the water get back into the circulation. Diuretics (like furosemide) help a lot. Can be diagnosed with an ultrasound scan of the heart (echo).
- venous insufficiency: if the veins cannot push the blood effectively towards the heart then gravity takes over and lets the much blood in the legs. This excess of blood leads to swollen legs. Raising the legs higher than the level of the heart, avoiding standing or sitting for too long and avoiding sun exposure helps. Can be diagnosed with an ultrasound scan of the leg veins (triplex).
- renal problems: loss of protein from the kidney makes the blood less capable to 'absorb' water from the tissues. Therefore water is more likely to move from the veins to the tissues than the opposite. Treatment of the renal condition is the answer. Raising the legs also helps. Can be diagnosed with simple blood and urine tests (for total protein and albumin).
- hypothyroidism: although thyroid problems are prevalent, getting swollen legs due to your thyroid would sound strange because it requires having serious thyroid disorder which should have been diagnosed earlier. TSH measurement (in the blood) is enough to diagnose it.
- specific problems: enlarged lymph nodes preventing lymph flow, infections, etc may also cause swollen legs. These problems require careful evaluation and specific treatment. It would take a really long answer to address all potential problems obviously, so I've mentioned the most common ones.

I hope you find my comments helpful!
You can contact me again, if you'd like any clarification or further information.

Kind Regards!

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