1st relax it is just bbq!
2nd keep your brisket nice and simple. Don't over think it. Season up the meat, put it on the fire. cook it till it is probe tender at the thickest part of the flat. Pull it off and let it vent heat off for 20mins, then wrap in foil/butcher paper and let it rest for 2 hours. Slice and enjoy.
Cooking time will vary at which temperatures you cook at. If you go low and slow at 225-235 you will probably be looking at 10+ hours of cooking. If you go medium pace 250-275 you will probably look at about 8-10 hours of cooking. If you go hot and fast at 300-325 you are going to be looking at about 5-7 hours of cooking.
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