If you suspect flooding or hydro-lock, pull the glow plug, close the throttle, and crank it with your electric starter for a second or two. The fuel in the combustion chamber will get sprayed out (so stay clear, and don't get sprayed in the face with it).

My tried and true method for starting up nitro engines is as follows:

1) Prime it - without the glow-starter installed, fully open the throttle, place a finger over the exhaust/muffler outlet, and crank the engine with your electric starter until you see some fuel start to spray into the carb (usually a little sprays up out of the carb as well).

2) Start it - lower the throttle to about 1/2-1/4, put the glow-starter on it, and crank the engine until it starts.

I'd say about 95% of the time, the engine fires right up for me.

Just be careful with the priming step. If you prime it too much, you'll get flooding and possibly hydro-lock. After you try this a few times, you get a feel for how much priming your engine needs to fire up.