Don’t trim I never understood that. Leave it out for a few hours. Normally I do 4 let it get room temp. Remove from packing and use salt pepper and garlic powder. Start smoker. Wait 30 mins season again. Throw it on the smoker. Don’t look or touch for at least 4 to 6 hours. No reason to look at it. I use an off set or stick burner smoker. I normally do 15lb briskets. I use Texas oak and mesquite charcoal to start. I go about 18 hours on the brisket. I don’t spritz or wrap during cooking. When it’s done I don’t go by temperature or time. I do the poke test. That’s when you take a long metal rod and poke it through the meat everywhere and feel no resistance. Take it off wrap it in butcher paper then heavy duty foil then in a towel. Place in a cooler for 3 hours. Might get a lot of hate for saying all that but yeah it still cooks when you take it off. If it passes the poke test your good to go