You just turn the ignition. You may have to push the clutch in for some cars, just like you have to push the break in for some automatic cars. Manual cars aren't as different as you think they are.
If you put someone who has developed their muscle memory driving automatic transmission vehicles behind the wheel of a manual transmission car, they will press the brake and turn the key.
Successfully starting a manual transmission vehicle has two prerequisites:
* knowing that you have to press the clutch in
* identifying the clutch
People without this knowledge lack these prerequisites.