The biggest thing is trying not to over-smoke it. Cold meat absorbs smoke best and they say that most of your smoke flavor will be gained in the first couple of hours. The rest of the time is spent in making it tender. The "KC Baron of BBQ" Paul Kirk always made a point of embarrassing those who use aluminum foil in the middle of the cooking process to keep moisture in and excess smoke out. He would whip out a foil-wrapped crutch and declare foil a "Texas Crutch." Nowadays, many of the top brisket cooks rely on pink butcher paper for much of the same effect, including Aaron Franklin in Austin and AZ's very own Scott Holmes of Little Miss BBQ fame. You can't argue with their results.
I personally don't practice what I preach and don't wrap briskets in anything. I cook on a Kamado and can control my smoke pretty easily because of a smaller fire and less smokewood. That and because I am lazy.