Edit the "splintercell2user.ini" file in the "\\splinter cell pandora tomorrow\\offline\\system" folder using a text editor. Bind one of the following codes to a function key and press it during game play to toggle the corresponding cheat function.
floating: fly
freeze enemies: playersonly
gives health: health
god mode: invincible 1
god mode off: invincible 0
more ammo: ammo
kills all enemies: killpawns
no clip mode: ghost
no clip off: walk
Sam is invisible: but enemies can still bump into him and start alerts. invisible 1
spawn airfoil round: summon echeloningredient.eringairfoilround
spawn disposable pick: summon echeloningredient.edisposablepick
spawn flashbang: summon echeloningredient.eflashbang
spawn frag grenade: summon echeloningredient.efraggrenade
spawn smoke grenade: summon echeloningredient.esmokegrenade
spawn sticky camera: summon echeloningredient.estickycamera
spawn sticky shocke: summon echeloningredient.estickyshocker
spawn wallmine: summon echeloningredient.ewallmine
turns off invisible: invisible 0
unfreeze enemies: playersonly 0

Editor's Note:
You should make a backup of any files you edit in case you need to restore the originals.