Agree with Willie...simple is best for a first time brisket smoke. You didn't say how big it was or how you plan to season, but like Willie, I like simple seasonings on beef. SPOG (salt, pepper, onion powder, garlic powder) is good...or maybe your favorite steak rub or montreal steak seasoning.
Be patient...depending on the size of that brisket, it could take 1 to 2 hours per raw pound to get done. You can cook at a smoker temp of anywhere from 225* to 275* (some go even hotter), but remember that your pellet cooker makes better smoke at lower temps...and it stands to reason that the lower you run your Traeger, the longer the total cooking time will be.
If you have a reliable probe-style meat thermometer, keep an eye on your internal temps (IT). When the IT starts getting close to 200*, periodically probe the meat with your probe or with a toothpick for tenderness (in several places), and when it glides in easily as into butter, its done!
If time allows, double-foil wrap it, then wrap in an old beach towel or old blanket and allow it to rest for at least an hour before slicing. Slice it across the grain of the meat and you'll have the most tender and tasty brisket you've ever had!
Good luck! Be sure to post up some Qview to show it off, and let us know how it turns out!
Red