Put the gas pedal to the floor and start cranking the key. You might have to crank it for awhile, but don't go TOO long (maybe 10-15 seconds tops). Don't be surprised if you get a backfire before it starts. This will help work the extra fuel out by pushing more air thru.
Personally, when dealing with a flooded, carbureated car, I like to keep my fire extinguisher close by, and the filter removed so the carb is open to the air, just in case it flames up thru the carb in the process. Not likely, but it happens.