A simple way to get the engines started:

Battery Switch - ON
DC Meter Selector - BAT
AC Meter Selector - APU GEN
Fuel Pump Switches - ON
APU Switch - START (it automatically flicks back to ON)
APU Generator Switches - ON (After APU is running)
APU Bleed Air Switch - ON
Gasper Fan - ON
Air Condition Packs - ON
Isolation Valve Switch - ON
Engine Bleed Air Switches - ON
Engine 1 Start Switch - GRD
After Engine 1 N2 RPM Percentage reaches 20 - Engine 1 Fuel Control Selector to START
Engine 2 Start Switch - GRD
After Engine 1 N2 RPM Percentage reaches 20 - Engine 2 Fuel Control Selector to START
Gen 1 & Gen 2 - ON
APU - OFF
DC Meter Selector - TR1 (or TR2/TR3)
AC Meter Selector - GEN 1 (or GEN 2)

That should have your engines running, you can now take the 737 for a flight.

I know there is more to do when preparing to fly the Captain Sim 737, but this is a simple way to get the engines started and taking it up for a spin. ;)