'OK then. When the car's runnin', you release the clutch pedal once you're in gear, until you 'ave to change it again.

This is hard. He's never had to teach someone to drive before and he's been doing it so long himself he can hardly remember what it was like to be clueless.

'Alright take 'er out of gear - do what you just did, only backwards. An' then...start 'er up.'

He'll go so far as to pray, if that'll keep his baby in one piece. Not out loud. But yeah, he's obviously nervous.