The only way to reduce it is to make sure your chimney height is correct for your installation (proper draft), your stove or fireplace has sufficient air for good combustion AND well seasoned proper wood.

Some woods burn with more smoke than others, dry seasoned wood with a low moisture content is the best.

From a survival standpoint, you don't want any undesirables to "see" your smoke, but one thing to keep in mind whether anyone sees it, they WILL smell it, and there are other things to consider.

Bad guy #1, "Those houses look abandoned, lets move on."

Bad guy #2, "I am not so sure...I think I caught a whif of wood smoke....Yep, look right there at the 3rd house, all the other roofs have snow all over, that one has a big bare dry spot a couple of feet around the chimney, someones home....mount up!"

Smoke is one thing....there are other variables unfortunatly.