Good choice in picking a complicated aeroplane to start, Krusty.
Let's look at a Metro 3.
Batteries on.
Check 22 volts.
Push the button marked 'start', then wait for the engine to start.
Hit the generator, wait for the amps to come down then turn it off again.
Hit the other start button, then at 10% turn the generator back on.
When it's finished starting, turn that generator on.
It's far more complicated to explain than do.
Oh, and they make it easy to shut the engines down, as they conveniently have two buttons marked STOP.