Hi,

Unless you alreadyb have the vacuum pump and gauges and an ample supply of r12, it's probably best to get it fixed at a reputable shop. The gauges, pump, and freon would probably cost you 50% to 100% of what it costs to do the job. You also need a leak detector, but could skip it if you were sure of where the leak was or used some sort of dye to identify or got a diagnosis at a shop and then did the fix work yourself.

Steve