Use the search button and read the many posts on this subject. There's at least 1/2 dozen ways to do this. I used the dial indicator technique, but as you'll see from the responses, I can't say with 100% certainty that I did it correctly, so use your own judgement here. Also, there may be another recommended method for the C280 (mine's a W126 380SE)
http://www.peachparts.com/shopforum/showthread.php?threadid=100590
As the job I did has only had a 500 mile drive for a 'test run', the proof in the pudding may not yet be evident. However, the bearing doesn't overheat, and no discernable noises to indicate a problem.
IMO, what I did is at least as good as trying to do the touchy-feely procedure by turning the hub until it's 'too tight to turn' or 'hard to turn' and backing off 1/2 or 1/3 turn on the nut, or rapping the mounted wheel until it 'sounds right' when the 'rattle' disappears.
It seems you either do it objectively with the dial indicator, or subjectively with the feel approach. Either way, it's a PITA to get it right by yourself with little or no prior experience.