I'm surprised some here say crank with ignition off to clear any oil.
I used to part own a Yak52 (Vendeneyef M14P 9-cylinder radial) and it was drummed into us to pull it though 10 blades by hand before starting. The M14P uses air start with an air distributer which turns the engine very slowly, but even that can damage the engine if it locks hydraulically.
That's where knowing your aircraft becomes important. In some aircraft, use of the starter motor is ill advised, while in others, it protects the engine. Where the starter motor is used to pull the engine through, it protects the motor because if liquid lock is present the starter clutch will slip. This will not work with all starter installations or systems.