mopping, injecting, foiling are not needed...especially for your first brisket.. too many variables will make it more challenging than you need to and you won't know what impact each had..good or bad.
use a good rub & keep steady temps without opening the door or lid to keep checking.
temps will likely be in the 180-195 range but rely on the feel of the brisket which is your ability to slide a probe, fork, knife etc into the meat without resistance.
XL BGE (#2) & Performer Platinum
Former owner: Jambo Backyard, Klose BYC, Lonestar Vertical offset w/ Insulated Firebox, Medium Spicewine, Pitts & Spitts, XL BGE (#1) & (2) Medium BGE's, 22" WSM & (2) 18" WSM's, 18" & 22" Weber Kettles