Here's what I do.
-I always check if my flight is oversold at
flyaow.com/classamex.htm or
seatcounter.com-If it is oversold I research all of the other routing options to find alternate flights on that airline and on other airlines, including alternate airports. A flight with many first class seats open is always a good alternate option.
-If it is oversold I make sure to get to the gate early (check-in agents can tell you if there is an oversell situation, but they don't have volunteer lists) and be first in line to speak to the GA and volunteer my seat. I always make it clear though that they should not give up the seat that I am holding until they are positive that there is an oversell situation.
-Some GA's give people without checked luggage priority for being bumped.
-Some GA's bump according to elite status rank, others bump to the friendliest volunteer...it's totally in the GA's hands so play nice
-Access to an airport lounge with free drinks/snacks/wi-fi/newspapers/showers, etc. make a long wait a whole lot more fun that waiting in a terminal!
-When being bumped I usually get a voucher for a free ticket or for an amount close to what I spent on the RT ticket, some airport food vouchers, and a confirmed first class seat on the next flight.
-If the next possible flight is the next day it would take a much larger voucher and a hotel room to make me want to get bumped.