yeah ill do it if i can do it on you too . PSN'S in sig.

Just play a team death match on Highrise.
at the start make a small dash to the window and look to your left across the map, your see lots of heads bounceing about and once you get a nack for sniping them you'll get lots of collaterals.

I got three collaterals (3/2/2) within 10 secs of a game

Kleszyk's way is one of the easiest but my favourite way is to go into a Domination on Skidrow and look down the little corridor at 'B'. I done this once and got FIVE different collateral's in the one game.