My favorite tactic is the plain old sneak toward the enemy. Right off the bat grab another experienced player and go directly towards the enemy. The point of the second player is he/she follows behind you(communicating in hand signals only) so if you get shot by walking in to them, he/she can get ready to take them out. Most likely the other team would have the same plan(maybe even the same route) so take all the time you need. Once you get close to the concentration of them pass them by about 15 yards and sneak in, I like to go for surrenders but most of the time it ends up that I mark a few guys and get shot, then the other guy stays back and picks them off as they go looking for more.
Sometimes I just snipe (pick them off from a concealed locale) and sometimes I just follow someone elses plan.