Left ankle swells like crazy. sit, stand, walk. no matter what it at least doubles size. no trouble with right ankle. what can i do to fix this?

See a doctor: To determine cause of the swelling. Compressive sock/anklet can be applied in the morning and see if that helps somewhat.

Have it evaluated: Ankle swelling especially only on one ankle is indicative of some inflammatory process: arthritis, tendonitis, fracture, sprain, or synovitis just to name a few. Get it checked out by a foot/ankle specialist and xrayed to make sure you're not doing more harm by doing nothing.