Start with the meat!
Short of going to your favorite local butcher, a solid plan if one is nearby, Costco seems to be able to pull first dibs on cuts coming from the larger producers. If you're eating vegetables...farmers market.
Pick the right spice.
Once your brisket is trimmed. Alright, you have to watch @divabbq on how to trim this thing. She'll save your party. Once your brisket is trimmed, the seasoning is critical to building the perfect bark, which is really the hallmark of a perfect brisket.
Cook it. Low and Slow.
This is the most important part, you have to cook these for a loooong time. The one below was cooked for 12 hours straight until I got an internal temperature of 203 degrees. Once you have the right internal temperature, wrap it in foil or butcher paper and let it rest for another 30 minutes. Be patient. Snack on some chips or something, but do not fill up until you cut this thing in pencil width strips.
Against the grain, eat the first burnt end but don't tell anyone ;)