Make sure your barrel is suitable for hevi-shot!! Some of the older guns aren't made for other than lead shot.
Why don't you scout around in the late afternoon and see what fields the geese are coming in to feed in. Once you know, get permission from the land owner, then go out and dig a pit in the area of the field where they were feeding. The pit should be big enough that you can squat down in it without throwing a shadow, on the field. Take some sheets from a newspaper, fold them in half. Spread them around the field, close to the pit, and put a clump of dirt on one end of each one, so it doesn't blow away. The dirt also gives a 3d image like a head may look from the air. There, now you've got your decoys set. The next morning get in the pit before light, and with whatever goose call you managed to buy yourself, blow a few hail calls when you see the first flights in the air. Don't call too much, and keep your head down till they are setting to land. This may work best in the earlier season, if the geese are decoy shy, but it does work.
About the pit. Spread whatever stubble might be in the field around on top of the fresh dug dirt, so it dosen't look like a big black doughnut from the air. If the field has been plowed than it probably won't make much difference. If there is snow in the field, take a white sheet to lie under, and save yourself the pit digging. Lay on some burlap. The newspaper works best on decoying snows but will bring in Canada's too. After your done shooting, throw the newspaper in the pit, and fill it in. "Always fill in your pit!" :-)