How do you install a Concentric flue exhaust for a furnace?

Best answer; hire a mechanical/Plumbing expert or contractor. This is a job if not tackled a by a pro, could cause your family great harm, brain damage, or death. Remember, you dealing with sealing out carbon monoxide, a oderless, tasteless gas. If not sealed out properly or if the material and sealing compounds used degenerate at anytime, the CO could easily enter your home and over time harm people and animals. If you have to ask this question, chances are you're not qualified or skilled enough to tackle this alone.