Step 1: Weapons
I recommended an Assault Rifle with an Underbarrel attachment. I would take the masterkey for room clearing, or the grenade launcher for corner campers. The Galil is the best fit for this, due to its excellent iron sights (you don't need an optical sight), and extra magazine size.
I recommended the RPG, if you have the grenade launcher. I recommend the China Lake if you equipped the Masterkey. Crossbow works for long distances. Don't use the M72 Law, as it is one shot.
Step 2: Perks
Sleight of Hand, to get your explosives off as fast as you can. Steady Aim is useless, because you need to aim down sights to shoot the rockets and noob tubes anyway.
Marathon Pro, but not with lightweight. Use it to sprint infinitly with your explosives. Hacker doesn't work if you have flak jacket.
Step 3: Grenades and Equipment
I recommend Nova Gas , to slow down your enemies. It gives you just enough time to aim down sights of your launcher.
I recommend C4, to get people around corners, and to use as a backup grenade.